General questions about Managed Service for Redis

• What is Managed Service for Redis?

• What part of database management and maintenance is Managed Service for Redis responsible for?

• Which tasks are best addressed using Managed Service for Redis, and which using VMs with databases?

• What is a database host and database cluster?

• How do I get started with Managed Service for Redis?

• How many database hosts can a cluster contain?

• How can I access a running DB host?

• How many clusters can I create within a single cloud?

• How are DB clusters maintained?

• Which Redis version does Managed Service for Redis use?

• What happens when a new DBMS version is released?

• What happens when a DBMS version becomes deprecated?

• How do you calculate usage cost for a database host?

• How can I change the computing resources and storage size for a database cluster?

• How do I fix the Maximum number of hosts reached error when adding a host to the cluster?

• Is database host backup enabled by default?

• When are backups performed? Is a database cluster available during a backup?

• What metrics and processes can be tracked using monitoring?

• How do I set up an alert that triggers as soon as a certain percentage of disk space has been used up?

• How do I get the logs of my actions in the services?

• Why is the cluster slow even though the computing resources are not used fully?

• Can I connect to cluster hosts via SSH or get superuser permissions on hosts?

What is Managed Service for Redis?What is Managed Service for Redis?

Managed Service for Redis is a service that helps you create, operate, and scale Redis databases in a cloud infrastructure.

With Managed Service for Redis, you can:

• Create a database with the required performance characteristics.
• Scale your processing power and storage size allocated to your databases as needed.
• Get database logs.

Managed Service for Redis takes on time-consuming Redis infrastructure administration tasks:

• Monitors resource usage.
• Automatically creates DB backups.
• Provides fault tolerance through automatic failover to backup replicas.
• Keeps database software updated.

You interact with database clusters in Managed Service for Redis the same way you interact with regular databases in your local infrastructure. This allows you to manage internal database settings to meet your app requirements.

What part of database management and maintenance is Managed Service for Redis responsible for?What part of database management and maintenance is Managed Service for Redis responsible for?

When you create clusters, Managed Service for Redis allocates resources, installs the DBMS, and creates databases.

For the created and running databases, Managed Service for Redis automatically creates backups and applies fixes and updates to the DBMS.

Managed Service for Redis also allows you to replicate data between database hosts (both within and across availability zones) and automatically routes the load to a backup replica in the event of a failure.

Which tasks are best addressed using Managed Service for Redis, and which using VMs with databases?Which tasks are best addressed using Managed Service for Redis, and which using VMs with databases?

Yandex Cloud offers two ways to work with databases:

• Managed Service for Redis allows you to operate template databases with no need to worry about administration.
• Yandex Compute Cloud virtual machines allow you to create and configure your own databases. This approach allows you to use any database management systems, access databases via SSH, etc.

What is a database host and database cluster?What is a database host and database cluster?

A database host is an isolated database environment in the cloud infrastructure with dedicated computing resources and reserved data storage.

A database cluster is one or more database hosts between which replication can be configured.

How do I get started with Managed Service for Redis?How do I get started with Managed Service for Redis?

Managed Service for Redis is available to any registered Yandex Cloud user.

To create a database cluster in Managed Service for Redis, you need to define its parameters:

• Host class (performance characteristics, such as CPUs, RAM, etc.).
• Disk type and size (reserved in full when creating a cluster).
• Network your cluster will be connected to.
• Number of hosts for the cluster and the availability zone for each host.

For more information, see Getting started.

How many database hosts can there be in one cluster?How many database hosts can there be in one cluster?

The minimum number of hosts per cluster depends on the following:

• Selected platform and host class.
• Selected disk type.
• Whether you enabled sharding when creating a cluster.

The maximum number of hosts in a cluster is only limited by the requested computing resources and the size of the storage for the cluster.

For more information, see Quotas and limits.

How can I access a running DB host?How can I access a running DB host?

You can connect to Managed Service for Redis databases using standard DBMS methods. However, there is one exception: Managed Service for Redis hosts can only be accessed from Yandex Cloud VMs connected to the same network.

How many clusters can I create within a single cloud?How many clusters can I create within a single cloud?

For more information on MDB technical and organizational limitations, see Quotas and limits.

How are DB clusters maintained?How are DB clusters maintained?

In Managed Service for Redis, maintenance implies:

• Automatic installation of DBMS updates and revisions for DB hosts (including disabled clusters).
• Changes to the host class and storage size.
• Other Managed Service for Redis maintenance activities.

For more information, see Maintenance.

Which Redis version does Managed Service for Redis use?Which Redis version does Managed Service for Redis use?

Managed Service for Redis supports Redis versions 6.2 and 7.0.

What happens when a new DBMS version is released?What happens when a new DBMS version is released?

The database software is updated when new minor versions are released. Owners of the affected DB clusters are notified of expected work times and DB availability in advance.

What happens when a DBMS version becomes deprecated?What happens when a DBMS version becomes deprecated?

One month after the database version becomes deprecated, Managed Service for Redis automatically sends email notifications to the owners of DB clusters created with this version.

New hosts can no longer be created using deprecated DBMS versions. Database clusters are automatically upgraded to the next supported version seven days after notification for minor versions and one month after notification for major versions. Deprecated major versions are going to be upgraded even if you have disabled automatic updates.

How do you calculate usage cost for a database host?How do you calculate usage cost for a database host?

In Managed Service for Redis, the usage cost is calculated based on the following parameters:

• Selected host class.
• Size of the storage reserved for the database host.
• Size of the database cluster backups. Backup size equal to the storage size is free of charge. Backup storage that exceeds this size is charged at special rates.
• Number of hours of database host operation. Partial hours are rounded to an integer value. You can find the cost per hour data for each host class in the Pricing policy section.

How can I change the computing resources and storage size for a database cluster?How can I change the computing resources and storage size for a database cluster?

You can change computing resources and storage size in the management console. All you need to do is choose a different host class for the required cluster.

The cluster characteristics change within 30 minutes. During this period, other maintenance activities may also be enabled for the cluster, such as installing updates.

How do I fix the error when adding a host to the cluster?How do I fix the Maximum number of hosts reached error when adding a host to the cluster?

This error occurs when adding a host to the Managed Service for Redis cluster with the b2.medium or b3-c1-m4 host class. In this case, change the host class. The cluster will become unavailable for about five to seven minutes. Then, add a host to the cluster.

Clusters with the b2.medium or b3-c1-m4 host class may contain only one host per cluster or shard. If you want to save a host class, after changing the class, you can add the host with the configuration you need and delete the previous host. Then, change the host class back to the initial one.

Is database host backup enabled by default?Is database host backup enabled by default?

Yes, backup is enabled by default. For Redis, a full backup takes place once a day and saves all DB cluster transaction logs. This allows you to restore the cluster state to any point in time during the backup storage period, except for the last 30 seconds.

By default, backups are stored for seven days.

When are backups performed? Is a database cluster available during backup?When are backups performed? Is a database cluster available during backup?

The backup window is an interval during which a full daily backup of the DB cluster is performed. The backup window is from 01:00 to 05:00 (UTC+3).

Clusters remain fully accessible during the backup window.

What metrics and processes can be tracked using monitoring?What metrics and processes can be tracked using monitoring?

For all DBMS types, you can track:

• CPU, memory, network, or disk usage, in absolute terms.
• Memory, network, or disk usage as a percentage of the set limits for the corresponding cluster host class.
• Amount of data in the DB cluster and the remaining free space in the data storage.

For DB hosts, you can track metrics specific to the corresponding type of DBMS. For example, for Redis, you can track:

• Average query execution time.
• Number of queries per second.
• Number of errors in logs, etc.

Monitoring can be performed with a minimum granularity of 5 seconds.

How do I set up an alert that triggers as soon as a certain percentage of disk space has been used up?How do I set up an alert that triggers as soon as a certain percentage of disk space has been used up?

Create an alert with the disk.used_bytes metric in Yandex Monitoring. This metric shows the disk space usage in the Managed Service for Redis cluster.

For disk.used_bytes, use notification thresholds. The recommended values are as follows:

• Alarm: 90% of the disk space
• Warning: 80% of the disk space

Thresholds are set in bytes only. For example, the recommended values for a 100 GB disk are as follows:

• Alarm: 96,636,764,160 bytes (90%)
• Warning: 85,899,345,920 bytes (80%)

Does the service meet the requirements under Russian Federation Federal Law No. 152-FZ on Personal Data?Does the service meet the requirements under Russian Federation Federal Law No. 152-FZ on Personal Data?

Yes, it does. You can read the full security audit conclusion.

Can I get logs of my operations with services?Can I get logs of my operations with services?

Yes, you can request log records about your resources from Yandex Cloud services. For more information, see Data requests.

What is the retention period for logs?What is the retention period for logs?

Cluster logs are stored for 30 days.

Why is the cluster slow even though the computing resources are not used fully?Why is the cluster slow even though the computing resources are not used fully?

Your storage may have insufficient maximum IOPS and bandwidth to process the current number of requests. In this case, throttling occurs, which degrades the entire cluster performance.

The maximum IOPS and bandwidth values increase by a fixed value when the storage size increases by a certain step. The step and increment values depend on the disk type:

Disk type	Step, GB	Max IOPS increase (read/write)	Max bandwidth increase (read/write), MB/s
network-ssd	32	1,000/1,000	15/15
network-ssd-nonreplicated	93	28,000/5,600	110/82

To increase the maximum IOPS and bandwidth values and make throttling less likely, increase the storage size when you update your cluster.

Consider switching to a faster disk type by restoring the cluster from a backup.

Can I connect to cluster hosts via SSH or get superuser permissions on hosts?Can I connect to cluster hosts via SSH or get superuser permissions on hosts?

You cannot connect to hosts via SSH, nor can you get superuser permissions. This is done for the sake of security and user cluster fault tolerance because direct changes inside a host can render it completely inoperable.