Chapter 5. Mirroring Ceph block devices As a storage administrator, you can add another layer of redundancy to Ceph block devices by mirroring data images between Red Hat Ceph Storage clusters. Understanding and using Ceph block device mirroring can provide you protection against data loss, such as a site failure. There are two configurations for mirroring Ceph block devices, one-way mirroring or two-way mirroring, and you can configure mirroring on pools and individual images. 5.1. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Network connectivity between the two storage clusters. Access to a Ceph client node for each Red Hat Ceph Storage cluster. 5.2. Ceph block device mirroring RADOS Block Device (RBD) mirroring is a process of asynchronous replication of Ceph block device images between two or more Ceph storage clusters. By locating a Ceph storage cluster in different geographic locations, RBD Mirroring can help you recover from a site disaster. Journal-based Ceph block device mirroring ensures point-in-time consistent replicas of all changes to an image, including reads and writes, block device resizing, snapshots, clones and flattening. RBD mirroring uses exclusive locks and the journaling feature to record all modifications to an image in the order in which they occur. This ensures that a crash-consistent mirror of an image is available. Important The CRUSH hierarchies supporting primary and secondary pools that mirror block device images must have the same capacity and performance characteristics, and must have adequate bandwidth to ensure mirroring without excess latency. For example, if you have X MB/s average write throughput to images in the primary storage cluster, the network must support N * X throughput in the network connection to the secondary site plus a safety factor of Y% to mirror N images. The rbd-mirror daemon is responsible for synchronizing images from one Ceph storage cluster to another Ceph storage cluster by pulling changes from the remote primary image and writes those changes to the local, non-primary image. The rbd-mirror daemon can run either on a single Ceph storage cluster for one-way mirroring or on two Ceph storage clusters for two-way mirroring that participate in the mirroring relationship. For RBD mirroring to work, either using one-way or two-way replication, a couple of assumptions are made: A pool with the same name exists on both storage clusters. A pool contains journal-enabled images you want to mirror. Important In one-way or two-way replication, each instance of rbd-mirror must be able to connect to the other Ceph storage cluster simultaneously. Additionally, the network must have sufficient bandwidth between the two data center sites to handle mirroring. One-way Replication One-way mirroring implies that a primary image or pool of images in one storage cluster gets replicated to a secondary storage cluster. One-way mirroring also supports replicating to multiple secondary storage clusters. On the secondary storage cluster, the image is the non-primary replicate; that is, Ceph clients cannot write to the image. When data is mirrored from a primary storage cluster to a secondary storage cluster, the rbd-mirror runs ONLY on the secondary storage cluster. For one-way mirroring to work, a couple of assumptions are made: You have two Ceph storage clusters and you want to replicate images from a primary storage cluster to a secondary storage cluster. The secondary storage cluster has a Ceph client node attached to it running the rbd-mirror daemon. The rbd-mirror daemon will connect to the primary storage cluster to sync images to the secondary storage cluster. Two-way Replication Two-way replication adds an rbd-mirror daemon on the primary cluster so images can be demoted on it and promoted on the secondary cluster. Changes can then be made to the images on the secondary cluster and they will be replicated in the reverse direction, from secondary to primary. Both clusters must have rbd-mirror running to allow promoting and demoting images on either cluster. Currently, two-way replication is only supported between two sites. For two-way mirroring to work, a couple of assumptions are made: You have two storage clusters and you want to be able to replicate images between them in either direction. Both storage clusters have a client node attached to them running the rbd-mirror daemon. The rbd-mirror daemon running on the secondary storage cluster will connect to the primary storage cluster to synchronize images to secondary, and the rbd-mirror daemon running on the primary storage cluster will connect to the secondary storage cluster to synchronize images to primary. Note As of Red Hat Ceph Storage 4, running multiple active rbd-mirror daemons in a single cluster is supported. Mirroring Modes Mirroring is configured on a per-pool basis with mirror peering storage clusters. Ceph supports two mirroring modes, depending on the type of images in the pool. Pool Mode All images in a pool with the journaling feature enabled are mirrored. Image Mode Only a specific subset of images within a pool are mirrored. You must enable mirroring for each image separately. Image States Whether or not an image can be modified depends on its state: Images in the primary state can be modified. Images in the non-primary state cannot be modified. Images are automatically promoted to primary when mirroring is first enabled on an image. The promotion can happen: Implicitly by enabling mirroring in pool mode. Explicitly by enabling mirroring of a specific image. It is possible to demote primary images and promote non-primary images. Additional Resources See the Image promotion and demotion section of the Red Hat Ceph Storage Block Device Guide for more details. 5.3. Configuring one-way mirroring using Ansible This procedure uses ceph-ansible to configure one-way replication of images on a primary storage cluster known as site-a , to a secondary storage cluster known as site-b . In the following examples, data is the name of the pool that contains the images to be mirrored. Prerequisites Two running Red Hat Ceph Storage clusters. A Ceph client node. A pool with the same name exists on both clusters. Images within the pool must have exclusive-lock and journaling enabled for journal-based mirroring. Note When using one-way replication, you can mirror to multiple secondary storage clusters. Procedure On the cluster where the images originate, enable the exclusive-lock and journaling features on an image. For new images , use the --image-feature option: Syntax Example For existing images , use the rbd feature enable command: Syntax Example To enable exclusive-lock and journaling on all new images by default, add the following setting to the Ceph configuration file: In the site-a cluster, complete the following steps: On a monitor node, create the user that the rbd-mirror daemon will use to connect to the cluster. The example creates a site-a user and outputs the key to a file named site-a.client.site-a.keyring : Syntax Example Copy the Ceph configuration file and the newly created key file from the monitor node to the site-b monitor and client nodes. Rename the Ceph configuration file from ceph.conf to CLUSTER-NAME .conf. In these examples, the file is /etc/ceph/site-a.conf . In the site-b cluster, complete the following steps: On the Ansible administration node, add an [rbdmirrors] group in the Ansible inventory file. The usual inventory file is /etc/ansible/hosts . Under the [rbdmirrors] group, add the name of the site-b client node on which the rbd-mirror daemon will run. The daemon will pull image changes from site-a to site-b . Navigate to the /usr/share/ceph-ansible/ directory: Create a new rbdmirrors.yml file by copying group_vars/rbdmirrors.yml.sample to group_vars/rbdmirrors.yml : Open the group_vars/rbdmirrors.yml file for editing. Set ceph_rbd_mirror_configure to true . Set ceph_rbd_mirror_pool to the pool in which you want to mirror images. In these examples, data is the name of the pool. By default, ceph-ansible configures mirroring using pool mode, which mirrors all images in a pool. Enable image mode where only images that have mirroring explicitly enabled are mirrored. To enable image mode, set ceph_rbd_mirror_mode to image : Set a name for the cluster that rbd-mirror will pull from. In these examples, the other cluster is site-a . On the Ansible administration node, set the user name of the key using ceph_rbd_mirror_remote_user . Use the same name you used when you created the key. In these examples the user is named client.site-a . As the ceph-ansible user, run the Ansible playbook: Bare-metal deployments: Container deployments: Explicitly enable mirroring on the desired images in both site-a and site-b clusters: Syntax Journal-based mirroring: Snapshot-based mirroring: Example Note Repeat this step whenever you want to mirror new image to peer cluster. Verify the mirroring status. Run the following command from a Ceph Monitor node in the site-b cluster: Example Journal-based mirroring: Snapshot-based mirroring: 1 1 If images are in the state up+replaying , then mirroring is functioning properly. Note Based on the connection between the sites, mirroring can take a long time to sync the images. 5.4. Configuring two-way mirroring using Ansible This procedure uses ceph-ansible to configure two-way replication so images can be mirrored in either direction between two clusters known as site-a and site-b . In the following examples, data is the name of the pool that contains the images to be mirrored. Note Two-way mirroring does not allow simultaneous writes to be made to the same image on either cluster. Images are promoted on one cluster and demoted on another. Depending on their status, they will mirror in one direction or the other. Prerequisites Two running Red Hat Ceph Storage clusters. Each cluster has a client node. A pool with the same name exists on both clusters. Images within the pool must have exclusive-lock and journaling enabled for journal-based mirroring. Procedure On the cluster where the images originate, enable the exclusive-lock and journaling features on an image. For new images , use the --image-feature option: Syntax Example For existing images , use the rbd feature enable command: Syntax Example To enable exclusive-lock and journaling on all new images by default, add the following setting to the Ceph configuration file: In the site-a cluster, complete the following steps: On a monitor node, create the user the rbd-mirror daemon will use to connect to the cluster. The example creates a site-a user and outputs the key to a file named site-a.client.site-a.keyring , and the Ceph configuration file is /etc/ceph/site-a.conf . Syntax Example Copy the keyring to the site-b cluster. Copy the file to the client node in the site-b cluster that the rbd-daemon will run on. Save the file to /etc/ceph/site-a.client.site-a.keyring : Syntax Example Copy the Ceph configuration file from the monitor node to the site-b monitor node and client nodes. The Ceph configuration file in this example is /etc/ceph/site-a.conf . Syntax Example In the site-b cluster, complete the following steps: Configure mirroring from site-a to site-b . On the Ansible administration node, add an [rbdmirrors] group in the Ansible inventory file, usually /usr/share/ceph-ansible/hosts . Under the [rbdmirrors] group, add the name of a site-b client node that the rbd-mirror daemon will run on. This daemon pulls image changes from site-a to site-b . Example Navigate to the /usr/share/ceph-ansible/ directory: Create a new rbdmirrors.yml file by copying group_vars/rbdmirrors.yml.sample to group_vars/rbdmirrors.yml : Open for editing the group_vars/rbdmirrors.yml file. Set ceph_rbd_mirror_configure to true , and set ceph_rbd_mirror_pool to the pool you want to mirror images in. In these examples, data is the name of the pool. By default, ceph-ansible configures mirroring using pool mode, which mirrors all images in a pool. Enable image mode where only images that have mirroring explicitly enabled are mirrored. To enable image mode, set ceph_rbd_mirror_mode to image : Set a name for the cluster that rbd-mirror in the group_vars/rbdmirrors.yml file. In these examples, the other cluster is site-a . On the Ansible administration node, set the user name of the key using ceph_rbd_mirror_remote_user in the group_vars/rbdmirrors.yml file. Use the same name you used when you created the key. In these examples the user is named client.site-a . As the ansible user, run the Ansible playbook: Bare-metal deployments: Container deployments: Verify the mirroring status. Run the following command from a Ceph Monitor node on the site-b cluster: Example Journal-based mirroring: Snapshot-based mirroring: 1 1 If images are in the state up+replaying , then mirroring is functioning properly. Note Based on the connection between the sites, mirroring can take a long time to sync the images. In the site-b cluster, complete the following steps. The steps are largely the same as above: On a monitor node, create the user the rbd-mirror daemon will use to connect to the cluster. The example creates a site-b user and outputs the key to a file named site-b.client.site-b.keyring , and the Ceph configuration file is /etc/ceph/site-b.conf . Syntax Example Copy the keyring to the site-a cluster. Copy the file to the client node in the site-a cluster that the rbd-daemon will run on. Save the file to /etc/ceph/site-b.client.site-b.keyring : Syntax Example Copy the Ceph configuration file from the monitor node to the site-a monitor node and client nodes. The Ceph configuration file in this example is /etc/ceph/site-b.conf . Syntax Example In the site-a cluster, complete the following steps: Configure mirroring from site-b to site-a . On the Ansible administration node, add an [rbdmirrors] group in the Ansible inventory file, usually /usr/share/ceph-ansible/hosts . Under the [rbdmirrors] group, add the name of a site-a client node that the rbd-mirror daemon will run on. This daemon pulls image changes from site-b to site-a . Example Navigate to the /usr/share/ceph-ansible/ directory: Create a new rbdmirrors.yml file by copying group_vars/rbdmirrors.yml.sample to group_vars/rbdmirrors.yml : Open for editing the group_vars/rbdmirrors.yml file. Set ceph_rbd_mirror_configure to true , and set ceph_rbd_mirror_pool to the pool you want to mirror images in. In these examples, data is the name of the pool. By default, ceph-ansible configures mirroring using pool mode which mirrors all images in a pool. Enable image mode where only images that have mirroring explicitly enabled are mirrored. To enable image mode, set ceph_rbd_mirror_mode to image : On the Ansible administration node, set a name for the cluster that rbd-mirror in the group_vars/rbdmirrors.yml file. Following the examples, the other cluster is named site-b . On the Ansible administration node, set the user name of the key using ceph_rbd_mirror_remote_user in group_vars/rbdmirrors.yml file. In these examples the user is named client.site-b . As the Ansible user on the administration node, run the Ansible playbook: Bare-metal deployments: Container deployments: Explicitly enable mirroring on the desired images in both site-a and site-b clusters: Syntax Journal-based mirroring: Snapshot-based mirroring: Example Note Repeat this step whenever you want to mirror new image to peer cluster. Verify the mirroring status. Run the following command from the client node on the site-a cluster: Example Journal-based mirroring: Snapshot-based mirroring: 1 1 The images should be in state up+stopped . Here, up means the rbd-mirror daemon is running and stopped means the image is not a target for replication from another cluster. This is because the images are primary on this cluster. 5.5. Configuring one-way mirroring using the command-line interface This procedure configures one-way replication of a pool from the primary storage cluster to a secondary storage cluster. Note When using one-way replication you can mirror to multiple secondary storage clusters. Note Examples in this section will distinguish between two storage clusters by referring to the primary storage cluster with the primary images as site-a , and the secondary storage cluster you are replicating the images to, as site-b . The pool name used in these examples is called data . Prerequisites A minimum of two healthy and running Red Hat Ceph Storage clusters. Root-level access to a Ceph client node for each storage cluster. A CephX user with administrator-level capabilities. Images within the pool must have exclusive-lock and journaling enabled for journal-based mirroring. Procedure Install the rbd-mirror package on the client node connected to the site-b storage cluster: Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Note The package is provided by the Red Hat Ceph Storage Tools repository. Enable the exclusive-lock, and journaling features on an image. For new images , use the --image-feature option: Syntax Example For existing images , use the rbd feature enable command: Syntax Example To enable exclusive-lock and journaling on all new images by default, add the following setting to the Ceph configuration file: Choose the mirroring mode, either pool or image mode. Important Use image mode for snapshot-based mirroring. Enabling pool mode : Syntax Example This example enables mirroring of the whole pool named data . Enabling image mode : Syntax Example This example enables image mode mirroring on the pool named data . Verify that mirroring has been successfully enabled: Syntax Example In the site-a cluster, complete the following steps: On the Ceph client node, create a user: Syntax Example Copy keyring to site-b cluster: Syntax Example On a Ceph client node, bootstrap the storage cluster peers. Register the storage cluster peer to the pool: Syntax Example Note This example bootstrap command creates the client.rbd-mirror-peer Ceph user. Copy the bootstrap token file to the site-b storage cluster. Syntax Example In the site-b cluster, complete the following steps: On the client node, create a user: Syntax Example Copy keyring to the site-a cluster, the Ceph client node: Syntax Example Import the bootstrap token: Syntax Example Note For one-way RBD mirroring, you must use the --direction rx-only argument, as two-way mirroring is the default when bootstrapping peers. Enable and start the rbd-mirror daemon on client node: Syntax Replace CLIENT_ID with the Ceph user created earlier. Example Important Each rbd-mirror daemon must have a unique Client ID. To verify the mirroring status, run the following command from a Ceph Monitor node in the site-a and site-b clusters: Syntax Example Journal-based mirroring: Snapshot-based mirroring: 1 1 Here, up means the rbd-mirror daemon is running, and stopped means this image is not the target for replication from another storage cluster. This is because the image is primary on this storage cluster. Example Journal-based mirroring: Snapshot-based mirroring: 1 1 If images are in the state up+replaying , then mirroring is functioning properly. Here, up means the rbd-mirror daemon is running, and replaying means this image is the target for replication from another storage cluster. Note Depending on the connection between the sites, mirroring can take a long time to sync the images. Additional Resources See the Ceph block device mirroring section in the Red Hat Ceph Storage Block Device Guide for more details. See the User Management section in the Red Hat Ceph Storage Administration Guide for more details on Ceph users. 5.6. Configuring two-way mirroring using the command-line interface This procedure configures two-way replication of a pool between the primary storage cluster, and a secondary storage cluster. Note When using two-way replication you can only mirror between two storage clusters. Note Examples in this section will distinguish between two storage clusters by referring to the primary storage cluster with the primary images as site-a , and the secondary storage cluster you are replicating the images to, as site-b . The pool name used in these examples is called data . Prerequisites A minimum of two healthy and running Red Hat Ceph Storage clusters. Root-level access to a Ceph client node for each storage cluster. A CephX user with administrator-level capabilities. Images within the pool must have exclusive-lock and journaling enabled for journal-based mirroring. Procedure Install the rbd-mirror package on the client node connected to the site-a storage cluster, and the client node connected to the site-b storage cluster: Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Note The package is provided by the Red Hat Ceph Storage Tools repository. Enable the exclusive-lock, and journaling features on an image. For new images , use the --image-feature option: Syntax Example For existing images , use the rbd feature enable command: Syntax Example To enable exclusive-lock and journaling on all new images by default, add the following setting to the Ceph configuration file: Choose the mirroring mode, either pool or image mode. Important Use image mode for snapshot-based mirroring. Enabling pool mode : Syntax Example This example enables mirroring of the whole pool named data . Enabling image mode : Syntax Example This example enables image mode mirroring on the pool named data . Verify that mirroring has been successfully enabled: Syntax Example In the site-a cluster, complete the following steps: On the Ceph client node, create a user: Syntax Example Copy keyring to site-b cluster: Syntax Example On a Ceph client node, bootstrap the storage cluster peers. Register the storage cluster peer to the pool: Syntax Example Note This example bootstrap command creates the client.rbd-mirror-peer Ceph user. Copy the bootstrap token file to the site-b storage cluster. Syntax Example In the site-b cluster, complete the following steps: On the client node, create a user: Syntax Example Copy keyring to the site-a cluster, the Ceph client node: Syntax Example Import the bootstrap token: Syntax Example Note The --direction argument is optional, as two-way mirroring is the default when bootstrapping peers. Enable and start the rbd-mirror daemon on the primary and secondary client nodes: Syntax Replace CLIENT_ID with the Ceph user created earlier. Example In the above example, users are enabled in the primary cluster site-a Example In the above example, users are enabled in the secondary cluster site-b Important Each rbd-mirror daemon must have a unique Client ID. To verify the mirroring status, run the following command from a Ceph Monitor node in the site-a and site-b clusters: Syntax Example Journal-based mirroring: Snapshot-based mirroring: 1 1 Here, up means the rbd-mirror daemon is running, and stopped means this image is not the target for replication from another storage cluster. This is because the image is primary on this storage cluster. Example Journal-based mirroring: Snapshot-based mirroring: 1 1 If images are in the state up+replaying , then mirroring is functioning properly. Here, up means the rbd-mirror daemon is running, and replaying means this image is the target for replication from another storage cluster. Note Depending on the connection between the sites, mirroring can take a long time to sync the images. Additional Resources See the Ceph block device mirroring section in the Red Hat Ceph Storage Block Device Guide for more details. See the User Management section in the Red Hat Ceph Storage Administration Guide for more details on Ceph users. 5.7. Administration for mirroring Ceph block devices As a storage administrator, you can do various tasks to help you manage the Ceph block device mirroring environment. You can do the following tasks: Viewing information about storage cluster peers. Add or remove a storage cluster peer. Getting mirroring status for a pool or image. Enabling mirroring on a pool or image. Disabling mirroring on a pool or image. Delaying block device replication. Promoting and demoting an image. 5.7.1. Prerequisites A minimum of two healthy running Red Hat Ceph Storage cluster. Root-level access to the Ceph client nodes. A one-way or two-way Ceph block device mirroring relationship. 5.7.2. Viewing information about peers View information about storage cluster peers. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To view information about the peers: Syntax Example 5.7.3. Enabling mirroring on a pool Enable mirroring on a pool by running the following commands on both peer clusters. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To enable mirroring on a pool: Syntax Example This example enables mirroring of the whole pool named data . Example This example enables image mode mirroring on the pool named data . Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.4. Disabling mirroring on a pool Before disabling mirroring, remove the peer clusters. Note When you disable mirroring on a pool, you also disable it on any images within the pool for which mirroring was enabled separately in image mode. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To disable mirroring on a pool: Syntax Example This example disables mirroring of a pool named data . Additional Resources See the Configuring image one-way mirroring section in the Red Hat Ceph Storage Block Device Guide for details. See the Removing a storage cluster peer section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.5. Enabling image mirroring Enable mirroring on the whole pool in image mode on both peer storage clusters. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure Enable mirroring for a specific image within the pool: Syntax Example This example enables mirroring for the image2 image in the data pool. Additional Resources See the Enabling mirroring on a pool section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.6. Disabling image mirroring Disable the mirror for images. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To disable mirroring for a specific image: Syntax Example This example disables mirroring of the image2 image in the data pool. 5.7.7. Image promotion and demotion Promote or demote an image. Note Do not force promote non-primary images that are still syncing, because the images will not be valid after the promotion. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To demote an image to non-primary: Syntax Example This example demotes the image2 image in the data pool. To promote an image to primary: Syntax Example This example promotes image2 in the data pool. Depending on which type of mirroring you are using, see either Recovering from a disaster with one-way mirroring or Recovering from a disaster with two-way mirroring for details. Use the --force option to force promote a non-primary image: Syntax Example Use forced promotion when the demotion cannot be propagated to the peer Ceph storage cluster. For example, because of cluster failure or communication outage. Additional Resources See the Failover after a non-orderly shutdown section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.8. Image resynchronization Re-synchronize an image. In case of an inconsistent state between the two peer clusters, the rbd-mirror daemon does not attempt to mirror the image that is causing the inconsistency. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To request a resynchronization to the primary image: Syntax Example This example requests resynchronization of image2 in the data pool. Additional Resources To recover from an inconsistent state because of a disaster, see either Recovering from a disaster with one-way mirroring or Recovering from a disaster with two-way mirroring for details. 5.7.9. Adding a storage cluster peer Add a storage cluster peer for the rbd-mirror daemon to discover its peer storage cluster. For example, to add the site-a storage cluster as a peer to the site-b storage cluster, then follow this procedure from the client node in the site-b storage cluster. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure Register the peer to the pool: Syntax Example 5.7.10. Removing a storage cluster peer Remove a storage cluster peer by specifying the peer UUID. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure Specify the pool name and the peer Universally Unique Identifier (UUID). Syntax Example Tip To view the peer UUID, use the rbd mirror pool info command. 5.7.11. Getting mirroring status for a pool Get the mirror status for a pool. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To get the mirroring pool summary: Syntax Example Tip To output status details for every mirroring image in a pool, use the --verbose option. 5.7.12. Getting mirroring status for a single image Get the mirror status for an image. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To get the status of a mirrored image: Syntax Example This example gets the status of the image2 image in the data pool. 5.7.13. Delaying block device replication Whether you are using one- or two-way replication, you can delay replication between RADOS Block Device (RBD) mirroring images. You might want to implement delayed replication if you want a window of cushion time in case an unwanted change to the primary image needs to be reverted before being replicated to the secondary image. To implement delayed replication, the rbd-mirror daemon within the destination storage cluster should set the rbd_mirroring_replay_delay = MINIMUM_DELAY_IN_SECONDS configuration option. This setting can either be applied globally within the ceph.conf file utilized by the rbd-mirror daemons, or on an individual image basis. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure To utilize delayed replication for a specific image, on the primary image, run the following rbd CLI command: Syntax Example This example sets a 10 minute minimum replication delay on image vm-1 in the vms pool. 5.7.14. Asynchronous updates and Ceph block device mirroring When updating a storage cluster using Ceph block device mirroring with an asynchronous update, follow the update instruction in the Red Hat Ceph Storage Installation Guide . Once updating is done, restart the Ceph block device instances. Note There is no required order for restarting the instances. Red Hat recommends restarting the instance pointing to the pool with primary images followed by the instance pointing to the mirrored pool. 5.7.15. Creating an image mirror-snapshot Create an image mirror-snapshot when it is required to mirror the changed contents of an RBD image when using snapshot-based mirroring. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Root-level access to the Ceph client nodes for the Red Hat Ceph Storage clusters. A CephX user with administrator-level capabilities. Access to the Red Hat Ceph Storage cluster where a snapshot mirror will be created. Important By default only 3 image mirror-snapshots can be created per image. The most recent image mirror-snapshot is automatically removed if the limit is reached. If required, the limit can be overridden through the rbd_mirroring_max_mirroring_snapshots configuration. Image mirror-snapshots are automatically deleted when the image is removed or when mirroring is disabled. Procedure To create an image-mirror snapshot: Syntax Example Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.16. Scheduling mirror-snapshots Mirror-snapshots can be automatically created when mirror-snapshot schedules are defined. The mirror-snapshot can be scheduled globally, per-pool or per-image levels. Multiple mirror-snapshot schedules can be defined at any level but only the most specific snapshot schedules that match an individual mirrored image will run. Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.17. Creating a mirror-snapshot schedule Create a mirror-snapshot schedule. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Root-level access to the Ceph client nodes for the Red Hat Ceph Storage clusters. A CephX user with administrator-level capabilities. Access to the Red Hat Ceph Storage cluster where a snapshot mirror will be created. Procedure To create a mirror-snapshot schedule: Syntax The interval can be specified in days, hours, or minutes using d, h, or m suffix respectively. The optional START_TIME can be specified using the ISO 8601 time format. Example Scheduling at image level: Scheduling at pool level: Scheduling at global level: Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.18. Listing all snapshot schedules at a specific level List all snapshot schedules at a specific level. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Root-level access to the Ceph client nodes for the Red Hat Ceph Storage clusters. A CephX user with administrator-level capabilities. Access to the Red Hat Ceph Storage cluster where a snapshot mirror will be created. Procedure To list all snapshot schedules for a specific global, pool or image level, with an optional pool or image name: Syntax Additionally, the `--recursive option can be specified to list all schedules at the specified level as shown below: Example Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.19. Removing a mirror-snapshot schedule Remove a mirror-snapshot schedule. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Root-level access to the Ceph client nodes for the Red Hat Ceph Storage clusters. A CephX user with administrator-level capabilities. Access to the Red Hat Ceph Storage cluster where a snapshot mirror will be created. Procedure To remove a mirror-snapshot schedule: Syntax The interval can be specified in days, hours, or minutes using d, h, m suffix respectively. The optional START_TIME can be specified using the ISO 8601 time format. Example Example Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.7.20. Viewing the status for the snapshots to be created View the status for the snapshots to be created for snapshot-based mirroring RBD images. Prerequisites A minimum of two healthy running Red Hat Ceph Storage clusters. Root-level access to the Ceph client nodes for the Red Hat Ceph Storage clusters. A CephX user with administrator-level capabilities. Access to the Red Hat Ceph Storage cluster where a snapshot mirror will be created. Procedure To view the status for the snapshots to be created: Syntax Example Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. 5.8. Recover from a disaster As a storage administrator, you can be prepared for eventual hardware failure by knowing how to recover the data from another storage cluster where mirroring was configured. In the examples, the primary storage cluster is known as the site-a , and the secondary storage cluster is known as the site-b . Additionally, the storage clusters both have a data pool with two images, image1 and image2 . 5.8.1. Prerequisites A running Red Hat Ceph Storage cluster. One-way or two-way mirroring was configured. 5.8.2. Disaster recovery Asynchronous replication of block data between two or more Red Hat Ceph Storage clusters reduces downtime and prevents data loss in the event of a significant data center failure. These failures have a widespread impact, also referred as a large blast radius , and can be caused by impacts to the power grid and natural disasters. Customer data needs to be protected during these scenarios. Volumes must be replicated with consistency and efficiency and also within Recovery Point Objective (RPO) and Recovery Time Objective (RTO) targets. This solution is called a Wide Area Network- Disaster Recovery (WAN-DR). In such scenarios it is hard to restore the primary system and the data center. The quickest way to recover is to failover the applications to an alternate Red Hat Ceph Storage cluster (disaster recovery site) and make the cluster operational with the latest copy of the data available. The solutions that are used to recover from these failure scenarios are guided by the application: Recovery Point Objective (RPO) : The amount of data loss, an application tolerate in the worst case. Recovery Time Objective (RTO) : The time taken to get the application back on line with the latest copy of the data available. Additional Resources See the Mirroring Ceph block devices section in the Red Hat Ceph Storage Block Device Guide for details. See the Encryption in transit section in the Red Hat Ceph Storage Data Security and Hardening Guide to know more about data transmission over the wire in an encrypted state. 5.8.3. Recover from a disaster with one-way mirroring To recover from a disaster when using one-way mirroring use the following procedures. They show how to fail over to the secondary cluster after the primary cluster terminates, and how to fail back. The shutdown can be orderly or non-orderly. Important One-way mirroring supports multiple secondary sites. If you are using additional secondary clusters, choose one of the secondary clusters to fail over to. Synchronize from the same cluster during fail back. 5.8.4. Recover from a disaster with two-way mirroring To recover from a disaster when using two-way mirroring use the following procedures. They show how to fail over to the mirrored data on the secondary cluster after the primary cluster terminates, and how to failback. The shutdown can be orderly or non-orderly. Additional Resources For details on demoting, promoting, and resyncing images, see the Configure mirroring on a image section in the Red Hat Ceph Storage Block Device Guide . 5.8.5. Failover after an orderly shutdown Failover to the secondary storage cluster after an orderly shutdown. Prerequisites Minimum of two running Red Hat Ceph Storage clusters. Root-level access to the node. Pool mirroring or image mirroring configured with one-way mirroring . Procedure Stop all clients that use the primary image. This step depends on which clients use the image. For example, detach volumes from any OpenStack instances that use the image. Demote the primary images located on the site-a cluster by running the following commands on a monitor node in the site-a cluster: Syntax Example Promote the non-primary images located on the site-b cluster by running the following commands on a monitor node in the site-b cluster: Syntax Example After some time, check the status of the images from a monitor node in the site-b cluster. They should show a state of up+stopped and be listed as primary: Resume the access to the images. This step depends on which clients use the image. Additional Resources See the Block Storage and Volumes chapter in the Red Hat OpenStack Platform Storage Guide . 5.8.6. Failover after a non-orderly shutdown Failover to secondary storage cluster after a non-orderly shutdown. Prerequisites Minimum of two running Red Hat Ceph Storage clusters. Root-level access to the node. Pool mirroring or image mirroring configured with one-way mirroring . Procedure Verify that the primary storage cluster is down. Stop all clients that use the primary image. This step depends on which clients use the image. For example, detach volumes from any OpenStack instances that use the image. Promote the non-primary images from a Ceph Monitor node in the site-b storage cluster. Use the --force option, because the demotion cannot be propagated to the site-a storage cluster: Syntax Example Check the status of the images from a Ceph Monitor node in the site-b storage cluster. They should show a state of up+stopping_replay and the description should say force promoted : Example Additional Resources See the Block Storage and Volumes chapter in the Red Hat OpenStack Platform Storage Guide . 5.8.7. Prepare for fail back If two storage clusters were originally configured only for one-way mirroring, in order to fail back, configure the primary storage cluster for mirroring in order to replicate the images in the opposite direction. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure On the client node of the site-a storage cluster, install the rbd-mirror package: Note The package is provided by the Red Hat Ceph Storage Tools repository. On the client node of the site-a storage cluster, specify the storage cluster name by adding the CLUSTER option to the /etc/sysconfig/ceph file: Copy the site-b Ceph configuration file and keyring file from the site-b Ceph Monitor node to the site-a Ceph Monitor and client nodes: Syntax Note The scp commands that transfer the Ceph configuration file from the site-b Ceph Monitor node to the site-a Ceph Monitor and client nodes renames the file to site-a.conf . The keyring file name stays the same. Copy the site-a keyring file from the site-a Ceph Monitor node to the site-a client node: Syntax Enable and start the rbd-mirror daemon on the site-a client node: Syntax Change CLIENT_ID to the Ceph Storage cluster user that the rbd-mirror daemon will use. The user must have the appropriate cephx access to the storage cluster. Example From the client node on the site-a cluster, add the site-b cluster as a peer: Example If you are using multiple secondary storage clusters, only the secondary storage cluster chosen to fail over to, and fail back from, must be added. From a monitor node in the site-a storage cluster, verify the site-b storage cluster was successfully added as a peer: Syntax Example Additional Resources For detailed information, see the User Management chapter in the Red Hat Ceph Storage Administration Guide . 5.8.7.1. Fail back to the primary storage cluster When the formerly primary storage cluster recovers, fail back to the primary storage cluster. Prerequisites Minimum of two running Red Hat Ceph Storage clusters. Root-level access to the node. Pool mirroring or image mirroring configured with one-way mirroring . Procedure Check the status of the images from a monitor node in the site-b cluster again. They should show a state of up-stopped and the description should say local image is primary : Example From a Ceph Monitor node on the site-a storage cluster determine if the images are still primary: Syntax Example In the output from the commands, look for mirroring primary: true or mirroring primary: false , to determine the state. Demote any images that are listed as primary by running a command like the following from a Ceph Monitor node in the site-a storage cluster: Syntax Example Resynchronize the images ONLY if there was a non-orderly shutdown. Run the following commands on a monitor node in the site-a storage cluster to resynchronize the images from site-b to site-a : Syntax Example After some time, ensure resynchronization of the images is complete by verifying they are in the up+replaying state. Check their state by running the following commands on a monitor node in the site-a storage cluster: Syntax Example Demote the images on the site-b storage cluster by running the following commands on a Ceph Monitor node in the site-b storage cluster: Syntax Example Note If there are multiple secondary storage clusters, this only needs to be done from the secondary storage cluster where it was promoted. Promote the formerly primary images located on the site-a storage cluster by running the following commands on a Ceph Monitor node in the site-a storage cluster: Syntax Example Check the status of the images from a Ceph Monitor node in the site-a storage cluster. They should show a status of up+stopped and the description should say local image is primary : Syntax Example 5.8.8. Remove two-way mirroring After fail back is complete, you can remove two-way mirroring and disable the Ceph block device mirroring service. Prerequisites A running Red Hat Ceph Storage cluster. Root-level access to the node. Procedure Remove the site-b storage cluster as a peer from the site-a storage cluster: Example Stop and disable the rbd-mirror daemon on the site-a client: Syntax Example

Commands:
rbd create IMAGE_NAME --size MEGABYTES --pool POOL_NAME --image-feature FEATURE[,FEATURE]
rbd create image1 --size 1024 --pool data --image-feature exclusive-lock,journaling
rbd feature enable POOL_NAME / IMAGE_NAME FEATURE_NAME
rbd feature enable data/image1 exclusive-lock,journaling
rbd_default_features = 125
ceph auth get-or-create client. CLUSTER_NAME mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/ CLUSTER_NAME .client. USER_NAME .keyring
ceph auth get-or-create client.site-a mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/site-a.client.site-a.keyring
[rbdmirrors] ceph-client
cd /usr/share/ceph-ansible
cp group_vars/rbdmirrors.yml.sample group_vars/rbdmirrors.yml
ceph_rbd_mirror_configure: true ceph_rbd_mirror_pool: "data"
ceph_rbd_mirror_mode: image
ceph_rbd_mirror_remote_cluster: "site-a"
ceph_rbd_mirror_remote_user: "client.site-a"
[user@admin ceph-ansible]USD ansible-playbook site.yml --limit rbdmirrors -i hosts
[ansible@admin ceph-ansible]USD ansible-playbook site-container.yml --limit rbdmirrors -i hosts
rbd mirror image enable POOL / IMAGE
rbd mirror image enable POOL / IMAGE snapshot
rbd mirror image enable data/image1 rbd mirror image enable data/image1 snapshot
rbd mirror image status data/image1 image1: global_id: 7d486c3f-d5a1-4bee-ae53-6c4f1e0c8eac state: up+replaying 1 description: replaying, master_position=[object_number=3, tag_tid=1, entry_tid=3], mirror_position=[object_number=3, tag_tid=1, entry_tid=3], entries_behind_master=0 last_update: 2019-04-22 13:19:27
rbd mirror image status data/image1 image1: global_id: 06acc9e6-a63d-4aa1-bd0d-4f3a79b0ae33 state: up+replaying 1 description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642689843,"remote_snapshot_timestamp":1642689843,"replay_state":"idle"} service: admin on ceph-rbd2-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:41:57
rbd create IMAGE_NAME --size MEGABYTES --pool POOL_NAME --image-feature FEATURE[,FEATURE]
rbd create image1 --size 1024 --pool data --image-feature exclusive-lock,journaling
rbd feature enable POOL_NAME / IMAGE_NAME FEATURE_NAME
rbd feature enable data/image1 exclusive-lock,journaling
rbd_default_features = 125
ceph auth get-or-create client. PRIMARY_CLUSTER_NAME mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/ PRIMARY_CLUSTER_NAME .client. USER_NAME .keyring -c /etc/ceph/ PRIMARY_CLUSTER_NAME .conf
ceph auth get-or-create client.site-a mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/site-a.client.site-a.keyring -c /etc/ceph/site-a.conf
scp /etc/ceph/ PRIMARY_CLUSTER_NAME .client. USER_NAME .keyring root@ SECONDARY_CLIENT_NODE_NAME :/etc/ceph/ PRIMARY_CLUSTER_NAME .client. USER_NAME .keyring
scp /etc/ceph/site-a.client.site-a.keyring root@client.site-b:/etc/ceph/site-a.client.site-a.keyring
scp /etc/ceph/ PRIMARY_CLUSTER_NAME .conf root@ SECONDARY_MONITOR_NODE_NAME :/etc/ceph/ PRIMARY_CLUSTER_NAME .conf scp /etc/ceph/ PRIMARY_CLUSTER_NAME .conf user@ SECONDARY_CLIENT_NODE_NAME :/etc/ceph/ PRIMARY_CLUSTER_NAME .conf
scp /etc/ceph/site-a.conf root@mon.site-b:/etc/ceph/site-a.conf scp /etc/ceph/site-a.conf user@client.site-b:/etc/ceph/site-a.conf
[rbdmirrors] client.site-b
[root@admin ~]USD cd /usr/share/ceph-ansible
cp group_vars/rbdmirrors.yml.sample group_vars/rbdmirrors.yml
ceph_rbd_mirror_configure: true ceph_rbd_mirror_pool: "data"
ceph_rbd_mirror_mode: image
ceph_rbd_mirror_remote_cluster: "site-a"
ceph_rbd_mirror_remote_user: "client.site-a"
[user@admin ceph-ansible]USD ansible-playbook site.yml --limit rbdmirrors -i hosts
[user@admin ceph-ansible]USD ansible-playbook site-container.yml --limit rbdmirrors -i hosts
rbd mirror image status data/image1 image1: global_id: 7d486c3f-d5a1-4bee-ae53-6c4f1e0c8eac state: up+replaying 1 description: replaying, master_position=[object_number=3, tag_tid=1, entry_tid=3], mirror_position=[object_number=3, tag_tid=1, entry_tid=3], entries_behind_master=0 last_update: 2021-04-22 13:19:27
rbd mirror image status data/image1 image1: global_id: 06acc9e6-a63d-4aa1-bd0d-4f3a79b0ae33 state: up+replaying 1 description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642689843,"remote_snapshot_timestamp":1642689843,"replay_state":"idle"} service: admin on ceph-rbd2-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:41:57
ceph auth get-or-create client. SECONDARY_CLUSTER_NAME mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/ SECONDARY_CLUSTER_NAME .client. USER_NAME .keyring -c /etc/ceph/ SECONDARY_CLUSTER_NAME .conf
ceph auth get-or-create client.site-b mon 'profile rbd' osd 'profile rbd pool=data' -o /etc/ceph/site-b.client.site-b.keyring -c /etc/ceph/site-b.conf
scp /etc/ceph/ SECONDARY_CLUSTER_NAME .client. USER_NAME .keyring root@ PRIMARY_CLIENT_NODE_NAME :/etc/ceph/ SECONDARY_CLUSTER_NAME .client. USER_NAME .keyring
scp /etc/ceph/site-b.client.site-b.keyring root@client.site-a:/etc/ceph/site-b.client.site-b.keyring
scp /etc/ceph/ SECONDARY_CLUSTER_NAME .conf root@ PRIMARY_MONITOR_NODE_NAME :/etc/ceph/ SECONDARY_CLUSTER_NAME .conf scp /etc/ceph/ SECONDARY_CLUSTER_NAME .conf user@ PRIMARY_CLIENT_NODE_NAME :/etc/ceph/ SECONDARY_CLUSTER_NAME .conf
scp /etc/ceph/site-b.conf root@mon.site-a:/etc/ceph/site-b.conf scp /etc/ceph/site-b.conf user@client.site-a:/etc/ceph/site-b.conf
[rbdmirrors] client.site-a
cd /usr/share/ceph-ansible
cp group_vars/rbdmirrors.yml.sample group_vars/rbdmirrors.yml
ceph_rbd_mirror_configure: true ceph_rbd_mirror_pool: "data"
ceph_rbd_mirror_mode: image
ceph_rbd_mirror_remote_cluster: "site-b"
ceph_rbd_mirror_remote_user: "client.site-b"
[user@admin ceph-ansible]USD ansible-playbook site.yml --limit rbdmirrors -i hosts
[user@admin ceph-ansible]USD ansible-playbook site-container.yml --limit rbdmirrors -i hosts
rbd mirror image enable POOL / IMAGE
rbd mirror image enable POOL / IMAGE snapshot
rbd mirror image enable data/image1 rbd mirror image enable data/image1 snapshot
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped 1 description: local image is primary last_update: 2021-04-16 15:45:31
rbd mirror image status data/image1 image1: global_id: 47fd1aae-5f19-4193-a5df-562b5c644ea7 state: up+stopped 1 description: local image is primary service: admin on ceph-rbd1-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:42:54 peer_sites: name: rbd-mirror.site-b state: up+replaying description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642693094,"remote_snapshot_timestamp":1642693094,"replay_state":"idle"} last_update: 2022-01-20 12:42:59 snapshots: 5 .mirror.primary.47fd1aae-5f19-4193-a5df-562b5c644ea7.dda146c6-5f21-4e75-ba93-660f6e57e301 (peer_uuids:[bfd09289-c9c9-40c8-b2d3-ead9b6a99a45])
yum install rbd-mirror
dnf install rbd-mirror
rbd create IMAGE_NAME --size MEGABYTES --pool POOL_NAME --image-feature FEATURE [,FEATURE]
rbd create image1 --size 1024 --pool data --image-feature exclusive-lock,journaling
rbd feature enable POOL_NAME / IMAGE_NAME FEATURE [, FEATURE ]
rbd feature enable data/image1 exclusive-lock,journaling
rbd_default_features = 125
rbd mirror pool enable POOL_NAME MODE
rbd mirror pool enable data pool
rbd mirror pool enable POOL_NAME MODE
rbd mirror pool enable data image
rbd mirror pool info POOL_NAME
rbd mirror pool info data Mode: image Site Name: 94cbd9ca-7f9a-441a-ad4b-52a33f9b7148 Peer Sites: none
ceph auth get-or-create client. PRIMARY_CLUSTER_NAME mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph. PRIMARY_CLUSTER_NAME .keyring
ceph auth get-or-create client.rbd-mirror.site-a mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph.client.rbd-mirror.site-a.keyring
scp /etc/ceph/ceph. PRIMARY_CLUSTER_NAME .keyring root@ SECONDARY_CLUSTER :_PATH_
scp /etc/ceph/ceph.client.rbd-mirror.site-a.keyring root@rbd-client-site-b:/etc/ceph/
rbd mirror pool peer bootstrap create --site-name LOCAL_SITE_NAME POOL_NAME > PATH_TO_BOOTSTRAP_TOKEN
rbd mirror pool peer bootstrap create --site-name rbd-mirror.site-a data > /root/bootstrap_token_rbd-mirror.site-a
scp PATH_TO_BOOTSTRAP_TOKEN root@ SECONDARY_CLUSTER :/root/
scp /root/bootstrap_token_site-a root@ceph-rbd2:/root/
ceph auth get-or-create client. SECONDARY_CLUSTER_NAME mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph. SECONDARY_CLUSTER_NAME .keyring
ceph auth get-or-create client.rbd-mirror.site-b mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph.client.rbd-mirror.site-b.keyring
scp /etc/ceph/ceph. SECONDARY_CLUSTER_NAME .keyring root@ PRIMARY_CLUSTER :_PATH_
scp /etc/ceph/ceph.client.rbd-mirror.site-b.keyring root@rbd-client-site-a:/etc/ceph/
rbd mirror pool peer bootstrap import --site-name LOCAL_SITE_NAME --direction rx-only POOL_NAME PATH_TO_BOOTSTRAP_TOKEN
rbd mirror pool peer bootstrap import --site-name rbd-mirror.site-b --direction rx-only data /root/bootstrap_token_rbd-mirror.site-a
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@rbd-mirror. CLIENT_ID systemctl start ceph-rbd-mirror@rbd-mirror. CLIENT_ID
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@rbd-mirror.site-a systemctl start ceph-rbd-mirror@rbd-mirror.site-a
rbd mirror image status POOL_NAME / IMAGE_NAME
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped 1 description: local image is primary last_update: 2021-04-22 13:45:31
rbd mirror image status data/image1 image1: global_id: 47fd1aae-5f19-4193-a5df-562b5c644ea7 state: up+stopped 1 description: local image is primary service: admin on ceph-rbd1-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:42:54 peer_sites: name: rbd-mirror.site-b state: up+replaying description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642693094,"remote_snapshot_timestamp":1642693094,"replay_state":"idle"} last_update: 2022-01-20 12:42:59 snapshots: 5 .mirror.primary.47fd1aae-5f19-4193-a5df-562b5c644ea7.dda146c6-5f21-4e75-ba93-660f6e57e301 (peer_uuids:[bfd09289-c9c9-40c8-b2d3-ead9b6a99a45])
rbd mirror image status data/image1 image1: global_id: 7d486c3f-d5a1-4bee-ae53-6c4f1e0c8eac state: up+replaying 1 description: replaying, master_position=[object_number=3, tag_tid=1, entry_tid=3], mirror_position=[object_number=3, tag_tid=1, entry_tid=3], entries_behind_master=0 last_update: 2021-04-22 14:19:27
rbd mirror image status data/image1 image1: global_id: 06acc9e6-a63d-4aa1-bd0d-4f3a79b0ae33 state: up+replaying 1 description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642689843,"remote_snapshot_timestamp":1642689843,"replay_state":"idle"} service: admin on ceph-rbd2-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:41:57
yum install rbd-mirror
dnf install rbd-mirror
rbd create IMAGE_NAME --size MEGABYTES --pool POOL_NAME --image-feature FEATURE [,FEATURE]
rbd create image1 --size 1024 --pool data --image-feature exclusive-lock,journaling
rbd feature enable POOL_NAME / IMAGE_NAME FEATURE [, FEATURE ]
rbd feature enable data/image1 exclusive-lock,journaling
rbd_default_features = 125
rbd mirror pool enable POOL_NAME MODE
rbd mirror pool enable data pool
rbd mirror pool enable POOL_NAME MODE
rbd mirror pool enable data image
rbd mirror pool info POOL_NAME
rbd mirror pool info data Mode: image Site Name: 94cbd9ca-7f9a-441a-ad4b-52a33f9b7148 Peer Sites: none
ceph auth get-or-create client. PRIMARY_CLUSTER_NAME mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph. PRIMARY_CLUSTER_NAME .keyring
ceph auth get-or-create client.rbd-mirror.site-a mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph.client.rbd-mirror.site-a.keyring
scp /etc/ceph/ceph. PRIMARY_CLUSTER_NAME .keyring root@ SECONDARY_CLUSTER :_PATH_
scp /etc/ceph/ceph.client.rbd-mirror.site-a.keyring root@rbd-client-site-b:/etc/ceph/
rbd mirror pool peer bootstrap create --site-name LOCAL_SITE_NAME POOL_NAME > PATH_TO_BOOTSTRAP_TOKEN
rbd mirror pool peer bootstrap create --site-name rbd-mirror.site-a data > /root/bootstrap_token_rbd-mirror.site-a
scp PATH_TO_BOOTSTRAP_TOKEN root@ SECONDARY_CLUSTER :/root/
scp /root/bootstrap_token_site-a root@ceph-rbd2:/root/
ceph auth get-or-create client. SECONDARY_CLUSTER_NAME mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph. SECONDARY_CLUSTER_NAME .keyring
ceph auth get-or-create client.rbd-mirror.site-b mon 'profile rbd-mirror' osd 'profile rbd' -o /etc/ceph/ceph.client.rbd-mirror.site-b.keyring
scp /etc/ceph/ceph. SECONDARY_CLUSTER_NAME .keyring root@ PRIMARY_CLUSTER :_PATH_
scp /etc/ceph/ceph.client.rbd-mirror.site-b.keyring root@rbd-client-site-a:/etc/ceph/
rbd mirror pool peer bootstrap import --site-name LOCAL_SITE_NAME --direction rx-tx POOL_NAME PATH_TO_BOOTSTRAP_TOKEN
rbd mirror pool peer bootstrap import --site-name rbd-mirror.site-b --direction rx-tx data /root/bootstrap_token_rbd-mirror.site-a
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@rbd-mirror. CLIENT_ID systemctl start ceph-rbd-mirror@rbd-mirror. CLIENT_ID
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@rbd-mirror.site-a systemctl start ceph-rbd-mirror@rbd-mirror.site-a systemctl enable ceph-rbd-mirror@rbd-mirror.site-b systemctl start ceph-rbd-mirror@rbd-mirror.site-b
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@rbd-mirror.site-a systemctl start ceph-rbd-mirror@rbd-mirror.site-a systemctl enable ceph-rbd-mirror@rbd-mirror.site-b systemctl start ceph-rbd-mirror@rbd-mirror.site-b
rbd mirror image status POOL_NAME / IMAGE_NAME
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped 1 description: local image is primary last_update: 2021-04-22 13:45:31
rbd mirror image status data/image1 image1: global_id: 47fd1aae-5f19-4193-a5df-562b5c644ea7 state: up+stopped 1 description: local image is primary service: admin on ceph-rbd1-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:42:54 peer_sites: name: rbd-mirror.site-b state: up+replaying description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642693094,"remote_snapshot_timestamp":1642693094,"replay_state":"idle"} last_update: 2022-01-20 12:42:59 snapshots: 5 .mirror.primary.47fd1aae-5f19-4193-a5df-562b5c644ea7.dda146c6-5f21-4e75-ba93-660f6e57e301 (peer_uuids:[bfd09289-c9c9-40c8-b2d3-ead9b6a99a45])
rbd mirror image status data/image1 image1: global_id: 7d486c3f-d5a1-4bee-ae53-6c4f1e0c8eac state: up+replaying 1 description: replaying, master_position=[object_number=3, tag_tid=1, entry_tid=3], mirror_position=[object_number=3, tag_tid=1, entry_tid=3], entries_behind_master=0 last_update: 2021-04-22 14:19:27
rbd mirror image status data/image1 image1: global_id: 06acc9e6-a63d-4aa1-bd0d-4f3a79b0ae33 state: up+replaying 1 description: replaying, {"bytes_per_second":0.0,"bytes_per_snapshot":0.0,"local_snapshot_timestamp":1642689843,"remote_snapshot_timestamp":1642689843,"replay_state":"idle"} service: admin on ceph-rbd2-vasi-43-5hwia4-node2 last_update: 2022-01-20 12:41:57
rbd mirror pool info POOL_NAME
rbd mirror pool info data Mode: pool Site Name: site-a Peer Sites: UUID: 950ddadf-f995-47b7-9416-b9bb233f66e3 Name: site-b Mirror UUID: 4696cd9d-1466-4f98-a97a-3748b6b722b3 Direction: rx-tx Client: client.site-b
rbd mirror pool enable POOL_NAME MODE
rbd mirror pool enable data pool
rbd mirror pool enable data image
rbd mirror pool disable POOL_NAME
rbd mirror pool disable data
rbd mirror image enable POOL_NAME / IMAGE_NAME
rbd mirror image enable data/image2
rbd mirror image disable POOL_NAME / IMAGE_NAME
rbd mirror image disable data/image2
rbd mirror image demote POOL_NAME / IMAGE_NAME
rbd mirror image demote data/image2
rbd mirror image promote POOL_NAME / IMAGE_NAME
rbd mirror image promote data/image2
rbd mirror image promote --force POOL_NAME / IMAGE_NAME
rbd mirror image promote --force data/image2
rbd mirror image resync POOL_NAME / IMAGE_NAME
rbd mirror image resync data/image2
rbd --cluster CLUSTER_NAME mirror pool peer add POOL_NAME PEER_CLIENT_NAME @ PEER_CLUSTER_NAME -n CLIENT_NAME
rbd --cluster site-b mirror pool peer add data client.site-a@site-a -n client.site-b
rbd mirror pool peer remove POOL_NAME PEER_UUID
rbd mirror pool peer remove data 7e90b4ce-e36d-4f07-8cbc-42050896825d
rbd mirror pool status POOL_NAME
rbd mirror pool status data health: OK images: 1 total
rbd mirror image status POOL_NAME / IMAGE_NAME
rbd mirror image status data/image2 image2: global_id: 703c4082-100d-44be-a54a-52e6052435a5 state: up+replaying description: replaying, master_position=[object_number=0, tag_tid=3, entry_tid=0], mirror_position=[object_number=0, tag_tid=3, entry_tid=0], entries_behind_master=0 last_update: 2019-04-23 13:39:15
rbd image-meta set POOL_NAME / IMAGE_NAME conf_rbd_mirroring_replay_delay MINIMUM_DELAY_IN_SECONDS
rbd image-meta set vms/vm-1 conf_rbd_mirroring_replay_delay 600
rbd --cluster CLUSTER_NAME mirror image snapshot POOL_NAME / IMAGE_NAME
root@rbd-client ~]# rbd --cluster site-a mirror image snapshot data/image1
rbd mirror snapshot schedule add --pool POOL_NAME --image IMAGE_NAME INTERVAL START_TIME
rbd mirror snapshot schedule add --pool data --image image1 6h
rbd mirror snapshot schedule add --pool data 24h 14:00:00-05:00
rbd mirror snapshot schedule add 48h
rbd --cluster site-a mirror snapshot schedule ls --pool POOL_NAME --recursive
rbd --cluster site-a mirror snapshot schedule ls --pool data --recursive POOL NAMESPACE IMAGE SCHEDULE data - - every 1d starting at 14:00:00-05:00 data - image1 every 6h
rbd --cluster CLUSTER_NAME mirror snapshot schedule remove POOL_NAME / IMAGE_NAME INTERVAL START_TIME
rbd --cluster site-a mirror snapshot schedule remove data/image1 6h
rbd --cluster site-a mirror snapshot schedule remove data/image1 24h 14:00:00-05:00
rbd --cluster site-a mirror snapshot schedule status POOL_NAME / IMAGE_NAME
rbd --cluster site-a mirror snapshot schedule status SCHEDULE TIME IMAGE 2020-02-26 18:00:00 data/image1
rbd mirror image demote POOL_NAME / IMAGE_NAME
rbd mirror image demote data/image1 rbd mirror image demote data/image2
rbd mirror image promote POOL_NAME / IMAGE_NAME
rbd mirror image promote data/image1 rbd mirror image promote data/image2
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped description: local image is primary last_update: 2019-04-17 16:04:37 rbd mirror image status data/image2 image2: global_id: 596f41bc-874b-4cd4-aefe-4929578cc834 state: up+stopped description: local image is primary last_update: 2019-04-17 16:04:37
rbd mirror image promote --force POOL_NAME / IMAGE_NAME
rbd mirror image promote --force data/image1 rbd mirror image promote --force data/image2
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopping_replay description: force promoted last_update: 2019-04-17 13:25:06 rbd mirror image status data/image2 image2: global_id: 596f41bc-874b-4cd4-aefe-4929578cc834 state: up+stopping_replay description: force promoted last_update: 2019-04-17 13:25:06
yum install rbd-mirror
CLUSTER=site-b
scp /etc/ceph/ceph.conf USER @ SITE_A_MON_NODE_NAME :/etc/ceph/site-b.conf scp /etc/ceph/site-b.client.site-b.keyring root@ SITE_A_MON_NODE_NAME :/etc/ceph/ scp /etc/ceph/ceph.conf user@ SITE_A_CLIENT_NODE_NAME :/etc/ceph/site-b.conf scp /etc/ceph/site-b.client.site-b.keyring user@ SITE_A_CLIENT_NODE_NAME :/etc/ceph/
scp /etc/ceph/site-a.client.site-a.keyring <user>@ SITE_A_CLIENT_HOST_NAME :/etc/ceph/
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@ CLIENT_ID systemctl start ceph-rbd-mirror@ CLIENT_ID
systemctl enable ceph-rbd-mirror.target systemctl enable ceph-rbd-mirror@site-a systemctl start ceph-rbd-mirror@site-a
rbd --cluster site-a mirror pool peer add data client.site-b@site-b -n client.site-a
rbd mirror pool info POOL_NAME
rbd mirror pool info data Mode: image Site Name: site-a Peer Sites: UUID: 950ddadf-f995-47b7-9416-b9bb233f66e3 Name: site-b Mirror UUID: 4696cd9d-1466-4f98-a97a-3748b6b722b3 Direction: rx-tx Client: client.site-b
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped description: local image is primary last_update: 2019-04-22 17:37:48 rbd mirror image status data/image2 image2: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped description: local image is primary last_update: 2019-04-22 17:38:18
rbd info POOL_NAME / IMAGE_NAME
rbd info data/image1 rbd info data/image2
rbd mirror image demote POOL_NAME / IMAGE_NAME
rbd mirror image demote data/image1
rbd mirror image resync POOL_NAME / IMAGE_NAME
rbd mirror image resync data/image1 Flagged image for resync from primary rbd mirror image resync data/image2 Flagged image for resync from primary
rbd mirror image status POOL_NAME / IMAGE_NAME
rbd mirror image status data/image1 rbd mirror image status data/image2
rbd mirror image demote POOL_NAME / IMAGE_NAME
rbd mirror image demote data/image1 rbd mirror image demote data/image2
rbd mirror image promote POOL_NAME / IMAGE_NAME
rbd mirror image promote data/image1 rbd mirror image promote data/image2
rbd mirror image status POOL_NAME / IMAGE_NAME
rbd mirror image status data/image1 image1: global_id: 08027096-d267-47f8-b52e-59de1353a034 state: up+stopped description: local image is primary last_update: 2019-04-22 11:14:51 rbd mirror image status data/image2 image2: global_id: 596f41bc-874b-4cd4-aefe-4929578cc834 state: up+stopped description: local image is primary last_update: 2019-04-22 11:14:51
rbd mirror pool peer remove data client.remote@remote --cluster local rbd --cluster site-a mirror pool peer remove data client.site-b@site-b -n client.site-a
systemctl stop ceph-rbd-mirror@ CLIENT_ID systemctl disable ceph-rbd-mirror@ CLIENT_ID systemctl disable ceph-rbd-mirror.target
systemctl stop ceph-rbd-mirror@site-a systemctl disable ceph-rbd-mirror@site-a systemctl disable ceph-rbd-mirror.target