Chapter 1. Preparing to install on OpenStack You can install OpenShift Container Platform on Red Hat OpenStack Platform (RHOSP). 1.1. Prerequisites You reviewed details about the OpenShift Container Platform installation and update processes. You read the documentation on selecting a cluster installation method and preparing it for users . 1.2. Choosing a method to install OpenShift Container Platform on OpenStack You can install OpenShift Container Platform on installer-provisioned or user-provisioned infrastructure. The default installation type uses installer-provisioned infrastructure, where the installation program provisions the underlying infrastructure for the cluster. You can also install OpenShift Container Platform on infrastructure that you provision. If you do not use infrastructure that the installation program provisions, you must manage and maintain the cluster resources yourself. See Installation process for more information about installer-provisioned and user-provisioned installation processes. 1.2.1. Installing a cluster on installer-provisioned infrastructure You can install a cluster on Red Hat OpenStack Platform (RHOSP) infrastructure that is provisioned by the OpenShift Container Platform installation program, by using one of the following methods: Installing a cluster on OpenStack with customizations : You can install a customized cluster on RHOSP. The installation program allows for some customization to be applied at the installation stage. Many other customization options are available post-installation . Installing a cluster on OpenStack in a restricted network : You can install OpenShift Container Platform on RHOSP in a restricted or disconnected network by creating an internal mirror of the installation release content. You can use this method to install a cluster that does not require an active internet connection to obtain the software components. You can also use this installation method to ensure that your clusters only use container images that satisfy your organizational controls on external content. 1.2.2. Installing a cluster on user-provisioned infrastructure You can install a cluster on RHOSP infrastructure that you provision, by using one of the following methods: Installing a cluster on OpenStack on your own infrastructure : You can install OpenShift Container Platform on user-provisioned RHOSP infrastructure. By using this installation method, you can integrate your cluster with existing infrastructure and modifications. For installations on user-provisioned infrastructure, you must create all RHOSP resources, like Nova servers, Neutron ports, and security groups. You can use the provided Ansible playbooks to assist with the deployment process. 1.3. Scanning RHOSP endpoints for legacy HTTPS certificates Beginning with OpenShift Container Platform 4.10, HTTPS certificates must contain subject alternative name (SAN) fields. Run the following script to scan each HTTPS endpoint in a Red Hat OpenStack Platform (RHOSP) catalog for legacy certificates that only contain the CommonName field. Important OpenShift Container Platform does not check the underlying RHOSP infrastructure for legacy certificates prior to installation or updates. Use the provided script to check for these certificates yourself. Failing to update legacy certificates prior to installing or updating a cluster will result in cluster dysfunction. Prerequisites On the machine where you run the script, have the following software: Bash version 4.0 or greater grep OpenStack client jq OpenSSL version 1.1.1l or greater Populate the machine with RHOSP credentials for the target cloud. Procedure Save the following script to your machine: #!/usr/bin/env bash set -Eeuo pipefail declare catalog san catalog="USD(mktemp)" san="USD(mktemp)" readonly catalog san declare invalid=0 openstack catalog list --format json --column Name --column Endpoints \ | jq -r '.[] | .Name as USDname | .Endpoints[] | select(.interface=="public") | [USDname, .interface, .url] | join(" ")' \ | sort \ > "USDcatalog" while read -r name interface url; do # Ignore HTTP if [[ USD{url#"http://"} != "USDurl" ]]; then continue fi # Remove the schema from the URL noschema=USD{url#"https://"} # If the schema was not HTTPS, error if [[ "USDnoschema" == "USDurl" ]]; then echo "ERROR (unknown schema): USDname USDinterface USDurl" exit 2 fi # Remove the path and only keep host and port noschema="USD{noschema%%/*}" host="USD{noschema%%:*}" port="USD{noschema##*:}" # Add the port if was implicit if [[ "USDport" == "USDhost" ]]; then port='443' fi # Get the SAN fields openssl s_client -showcerts -servername "USDhost" -connect "USDhost:USDport" </dev/null 2>/dev/null \ | openssl x509 -noout -ext subjectAltName \ > "USDsan" # openssl returns the empty string if no SAN is found. # If a SAN is found, openssl is expected to return something like: # # X509v3 Subject Alternative Name: # DNS:standalone, DNS:osp1, IP Address:192.168.2.1, IP Address:10.254.1.2 if [[ "USD(grep -c "Subject Alternative Name" "USDsan" || true)" -gt 0 ]]; then echo "PASS: USDname USDinterface USDurl" else invalid=USD((invalid+1)) echo "INVALID: USDname USDinterface USDurl" fi done < "USDcatalog" # clean up temporary files rm "USDcatalog" "USDsan" if [[ USDinvalid -gt 0 ]]; then echo "USD{invalid} legacy certificates were detected. Update your certificates to include a SAN field." exit 1 else echo "All HTTPS certificates for this cloud are valid." fi Run the script. Replace any certificates that the script reports as INVALID with certificates that contain SAN fields. Important You must replace all legacy HTTPS certificates before you install OpenShift Container Platform 4.10 or update a cluster to that version. Legacy certificates will be rejected with the following message: x509: certificate relies on legacy Common Name field, use SANs instead 1.3.1. Scanning RHOSP endpoints for legacy HTTPS certificates manually Beginning with OpenShift Container Platform 4.10, HTTPS certificates must contain subject alternative name (SAN) fields. If you do not have access to the prerequisite tools that are listed in "Scanning RHOSP endpoints for legacy HTTPS certificates", perform the following steps to scan each HTTPS endpoint in a Red Hat OpenStack Platform (RHOSP) catalog for legacy certificates that only contain the CommonName field. Important OpenShift Container Platform does not check the underlying RHOSP infrastructure for legacy certificates prior to installation or updates. Use the following steps to check for these certificates yourself. Failing to update legacy certificates prior to installing or updating a cluster will result in cluster dysfunction. Procedure On a command line, run the following command to view the URL of RHOSP public endpoints: USD openstack catalog list Record the URL for each HTTPS endpoint that the command returns. For each public endpoint, note the host and the port. Tip Determine the host of an endpoint by removing the scheme, the port, and the path. For each endpoint, run the following commands to extract the SAN field of the certificate: Set a host variable: USD host=<host_name> Set a port variable: USD port=<port_number> If the URL of the endpoint does not have a port, use the value 443 . Retrieve the SAN field of the certificate: USD openssl s_client -showcerts -servername "USDhost" -connect "USDhost:USDport" </dev/null 2>/dev/null \ | openssl x509 -noout -ext subjectAltName Example output X509v3 Subject Alternative Name: DNS:your.host.example.net For each endpoint, look for output that resembles the example. If there is no output for an endpoint, the certificate of that endpoint is invalid and must be re-issued. Important You must replace all legacy HTTPS certificates before you install OpenShift Container Platform 4.10 or update a cluster to that version. Legacy certificates are rejected with the following message: x509: certificate relies on legacy Common Name field, use SANs instead

Commands:
#!/usr/bin/env bash set -Eeuo pipefail declare catalog san catalog="USD(mktemp)" san="USD(mktemp)" readonly catalog san declare invalid=0 openstack catalog list --format json --column Name --column Endpoints | jq -r '.[] | .Name as USDname | .Endpoints[] | select(.interface=="public") | [USDname, .interface, .url] | join(" ")' | sort > "USDcatalog" while read -r name interface url; do # Ignore HTTP if [[ USD{url#"http://"} != "USDurl" ]]; then continue fi # Remove the schema from the URL noschema=USD{url#"https://"} # If the schema was not HTTPS, error if [[ "USDnoschema" == "USDurl" ]]; then echo "ERROR (unknown schema): USDname USDinterface USDurl" exit 2 fi # Remove the path and only keep host and port noschema="USD{noschema%%/*}" host="USD{noschema%%:*}" port="USD{noschema##*:}" # Add the port if was implicit if [[ "USDport" == "USDhost" ]]; then port='443' fi # Get the SAN fields openssl s_client -showcerts -servername "USDhost" -connect "USDhost:USDport" </dev/null 2>/dev/null | openssl x509 -noout -ext subjectAltName > "USDsan" # openssl returns the empty string if no SAN is found. # If a SAN is found, openssl is expected to return something like: # # X509v3 Subject Alternative Name: # DNS:standalone, DNS:osp1, IP Address:192.168.2.1, IP Address:10.254.1.2 if [[ "USD(grep -c "Subject Alternative Name" "USDsan" || true)" -gt 0 ]]; then echo "PASS: USDname USDinterface USDurl" else invalid=USD((invalid+1)) echo "INVALID: USDname USDinterface USDurl" fi done < "USDcatalog" clean up temporary files rm "USDcatalog" "USDsan" if [[ USDinvalid -gt 0 ]]; then echo "USD{invalid} legacy certificates were detected. Update your certificates to include a SAN field." exit 1 else echo "All HTTPS certificates for this cloud are valid." fi
x509: certificate relies on legacy Common Name field, use SANs instead
openstack catalog list
host=<host_name>
port=<port_number>
openssl s_client -showcerts -servername "USDhost" -connect "USDhost:USDport" </dev/null 2>/dev/null | openssl x509 -noout -ext subjectAltName
X509v3 Subject Alternative Name: DNS:your.host.example.net
x509: certificate relies on legacy Common Name field, use SANs instead