TencentDB for Redis

TencentDB for Redis
FAQs
Product Documentation©2013-2022 Tencent Cloud. All rights reserved.

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TencentDB for Redis

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TencentDB for RedisContentsFAQs
GeneralConnection and LoginPurchase©2013-2022 Tencent Cloud. All rights reserved.

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TencentDB for Redis

FAQs
General：Last updated 2023-01-30 10:43:51

How do I use the hash algorithm of TencentDB for Redis Cluster Edition?
The hash algorithm of the Redis Cluster Edition is the same as that in the a Redis Community Edition cluster, i.e.,
HASH_SLOT = CRC16(key) mod 16384 . For more information, see Redis Cluster Specification.

What is the maximum capacity of a single instance?
EditionSpecification Range

Memory Edition (Standard Architecture)

0.25 GB–64 GB

Memory Edition (Cluster Architecture)

2 GB–8 TBCKV Edition (Standard Architecture)

4 GB–384 GB

CKV Edition (Cluster Architecture)

12 GB–48 TB

Is the data stored in TencentDB for Redis reliable?
Redis Standard Architecture (zero-replica) does not provide high availability. Other editions of Redis adopt amaster/replica replication structure, where data reliability is ensured by hot backup plus daily cold backup of the data.

Which persistence method does TencentDB for Redis use?
On the TencentDB for Redis backend, the backup cluster performs full data backup, and persistence is done on thereplicas which is virtually imperceptible to the online business.

Why is 2 MB of storage capacity used right after an instance is purchased?
That is used by the TencentDB for Redis instance in maintaining its data structure.

Can TencentDB for Redis be managed with visual tools such as Redis Desktop Manager?
You can perform Ops and management operations in the TencentDB for Redis console. If you need to use a visualtool, use a CVM instance as a jump server to provide an access address for Redis Desktop Manager.

Will my business be interrupted during scaling?
Momentary disconnections during scaling of different editions of TencentDB for Redis are as describe below:©2013-2022 Tencent Cloud. All rights reserved.

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TencentDB for Redis

During scale-up, if the expanded capacity exceeds the remaining capacity of a single server, the cluster will performsharding or migrate nodes, and a momentary business disconnection will occur; otherwise, no disconnections willoccur.
During scale-out, the number of nodes in the cluster will be increased, and a momentary business disconnection willoccur.
During scale-in, node repossession will cause node migration in the cluster, and a momentary business disconnection
will occur.
During scale-down, no momentary business disconnections will occur.

How do I add a monitoring alarm?
This can be implemented through custom monitoring and alarming. For more information, see Monitoring at FiveSecond Granularity.

Do I need to purchase different instances for selecting 0–15 databases?
No. Multiple databases can be set on one Standard Architecture or Cluster Architecture instance.

Does TencentDB for Redis support Lua?
For Redis Memory Edition (Standard Architecture) instances purchased before September 1, 2018, Lua is notenabled by default, and you can submit a ticket for application. For instances purchased after that date, Lua isenabled by default.
Redis Memory Edition (Cluster Architecture), CKV Edition (Standard Architecture), and CKV Edition (ClusterArchitecture) instances have Lua enabled by default.

Does TencentDB for Redis support caching invalidated subscription events?
Yes.

What should I do if I accidentally delete my account or forget the password?
If you accidentally deleted an account, you can log in to the TencentDB for Redis console, click an instance ID to enter
the instance management page, and select Account Management > Create Account to create a new account.
If you forgot the password of the default account, you can reset it by locating the corresponding account on theAccount Management page.

What should I do if the data on a replica node is out of sync with the data on the masternode in TencentDB for Redis?
Updates of the TencentDB for Redis master node will be automatically replicated to its associated replica node. Due
to Redis' async replication mechanism, replica node updates may lag behind the master node updates. Possible
causes are as follows:
The I/O write volume of the master node exceeds the sync speed of the replica node.

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TencentDB for Redis

There is a network delay between the master node and the replica node.

How do I check the port connectivity of TencentDB for Redis?
You can use the telnet command to check the port connectivity.

How do I set a caching policy in TencentDB for Redis?
Log in to the TencentDB for Redis console, click an instance ID in the instance list to enter the parameter configuration
page, and configure a caching policy through the maxmemory-policy parameter, whose default value isnoeviction .

How do I download a client for TencentDB for Redis?
Clients compatible with the Redis protocol can access TencentDB for Redis. You can choose an appropriate client asneeded. For the download addresses, see Clients.

How do I upgrade the version of TencentDB for Redis?
Log in to the TencentDB for Redis console and click an instance ID in the instance list to enter the Instance Details
page, where you can upgrade the instance version. For more information, see Upgrading Instance Version.

How do I upgrade the architecture of TencentDB for Redis?
Log in to the TencentDB for Redis console and click an instance ID in the instance list to enter the Instance Details
page, where you can upgrade the instance architecture. For more information, see Upgrading Instance Architecture.

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TencentDB for RedisConnection and Login：

Last updated 2024-03-21 11:10:11

How do I connect to a TencentDB for Redis instance?
You can connect to a TencentDB for Redis instance using a client tool, DMC, and SDKs supporting various
programing languages. For more information, see Connecting to TencentDB for Redis Instance.

What should I do if the connection to TencentDB for Redis failed?
Common causes of connection failure: Network/security group issues, password issues, and connection issues (i.e.,the maximum number of connections has been reached). For corresponding solutions, see Redis Instance Connection
Failure.

How can TencentDB for Redis support private network access? How do I view the private
network address of my instance?
To support private network access, the CVM and TencentDB instances must be under the same account and in thesame VPC in the same region, or both in the classic network.
To view the private network address, log in to the TencentDB for Redis console and view the address in the instancelist, or click an instance ID and view the address on the displayed instance details page.

Can my CVM instance connect to TencentDB for Redis over private network?
1. The following conditions must be met to use the private network connection:
The CVM and TencentDB instances must be under the same account and in the same VPC in the same region, orboth in the classic network.
2. You can check whether they are in the same VPC or both in the classic network in the following ways:
You can log in to the CVM console, and view the network information of a CVM instance in the instance list or on theinstance details page.
You can log in to the TencentDB for Redis console, and view the network information of a Redis instance in theinstance list or on the instance details page.
For more information, see Redis Instance Connection Failure.

What should I do if my CVM and TencentDB for Redis instances are in different VPCs?
You can connect to instances through CCN.
CVM and TencentDB instances in different VPCs (under the same or different accounts in the same or differentregions) can be interconnected over the private network through Cloud Connect Network.

My CVM and TencentDB for Redis instances are in different regions (such as Guangzhouand Shanghai, respectively). Can I use a private network for connection?

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TencentDB for RedisIf CVM and Redis instances are in different regions, they are in different VPCs, so they cannot interconnect directly
over private network. We recommend that you use CCN to connect the VPCs.

My CVM and TencentDB for Redis instances are in different AZs (such as Shanghai Zone 2and Shanghai Zone 1, respectively) in the same region. Can I use a private network forconnection?
Even if the CVM and TencentDB for Redis instances are in the same region, they may be in different VPCs.
If they are in different AZs in the same VPC, they can interconnect over private network.
If they are in different VPCs (such as VPC 1 and VPC 2, respectively), they cannot interconnect over the privatenetwork. For solutions, see Changing Network.

My CVM and TencentDB for Redis instances are in different AZs (such as Shanghai Zone 2and Shanghai Zone 1, respectively) in the same VPC. Can I use a private network forconnection?
Yes. Instances in different AZs but in the same VPC interconnect over private network by default.

My CVM and TencentDB for Redis instances are under different accounts. Can I use aprivate network for connection?
No. Because instances under different accounts are in different VPCs. We recommend that you use CCN forconnection.

How do I enable access to Redis over public network?
For more information, see Configuring Public Network Address.

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TencentDB for RedisPurchase：Last updated 2023-05-23 10:40:47

How do I select an appropriate TencentDB for Redis instance specification?
The TencentDB for Redis specification can be selected based on two factors: capacity and performance. The capacity
is determined according to the data storage needs. For more information on the performance, see PerformanceMetrics.

Which regions are supported by TencentDB for Redis?
As an infrastructure, TencentDB for Redis supports regions where CVM instances are deployed. For more
information, see Regions and AZs.

How is TencentDB for Redis charged?
It is pay-as-you-go. For more information, see Pricing.

What are the performance metrics of TencentDB for Redis?
TencentDB for Redis is available in Standard Architecture and Cluster Architecture. For QPS requirements between
80,000 and 120,000, you can choose the Standard Architecture. For a higher QPS performance, use the Cluster
Architecture.

What versions does TencentDB for Redis support?
Currently, it is compatible with Redis 2.8, 4.0, and 5.0.

How do I request a refund for a purchased instance if I don’t need it anymore?
You can request a refund based on your instance type:Pay-as-you-go (postpaid): TencentDB for RedisL resources will be directly returned without refund.
You can return instances in the instance list in the TencentDB for Redis console in a self-service manner. For more
information, see Returning and Isolating Instance.

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