Inspections and recommendations in Yandex StoreDoc

Managed database clusters regularly undergo diagnostics to detect possible issues, increase the cluster's reliability, and improve its performance. The results of such checks are displayed as inspections under Recommendations. You can see notifications about successful checks and recommendations on eliminating discovered risks. The responsibility to troubleshoot any detected issues lies within the Yandex Cloud user's remit.

All checks have a severity level:

• High level: Criteria of high cluster availability, significant risks of reduced performance, data loss risks. Such checks warrant special attention and require following the recommendations provided.
• Moderate level: Possible risks of reduced performance, suboptimal memory and disk space usage.
• Low level: Potential risks and cluster operation limitations.

The list of recommendations is updated regularly. For each recommendation, the following timestamps are fixed: the date of the risk's first detection and the date of the most recent status update on this issue. If the recommendation seems to be excessive or incorrect, you can hide it, specifying a reason. Once the hiding period expires, the recommendation will automatically become available again if the issue persists.

Recommendations are available at the cluster, folder, and cloud levels and provide tips for all your resources. However, the absence of recommendations does not mean that your cluster is optimized: the list of checks gets continuously appended but still remains incomprehensive and cannot replace monitoring, since it is targeted at detecting patterns rather than specific issues. You can additionally run cluster performance diagnostics and analyze monitoring metrics.

Managing recommendations in Yandex StoreDoc requires the managed-mongodb.editor role or higher.

Available inspections in Yandex StoreDocAvailable inspections in Yandex StoreDoc

Category	Check	Risk	Severity
Performance	CPU usage	Risk of reduced performance	High
High availability	Availability of replicas in a shard	Risk of data loss and cluster unavailability in the event of a zone failure (lack of replicas)	Low
High availability	High cluster availability during zone failure	Risk of data loss and cluster unavailability in the event of a zone failure	High
High availability	Allocating disk space	Risk of cluster unavailability	High
High availability	Memory allocation	Lack of RAM	High
High availability	Database version updates	Database version is out of date	High
High availability	Replication lag	Risk of data loss	Moderate
High availability	Disk autoscaling feature	Disk space autoscaling is limited	Moderate

Risk of reduced performanceRisk of reduced performance

Description

The host continuously uses all CPU resources, which may cause delays in query processing. Check the load and optimize your queries (which may include using the WebSQL AI assistant) or increase computing resources of the cluster.

Action

To increase the cluster's computing resources:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. Under Resources, select a host class with the required amount of vCPUs.
4. Click Save changes.

Risk of data loss and cluster unavailability in the event of a zone (replica) failureRisk of data loss and cluster unavailability in the event of a zone (replica) failure

Description

Your shards have no replicas, posing a risk of data loss and cluster unavailability. To ensure high availability, add replicas in a different zone for the specified shards.

Action

To migrate hosts from one availability zone to another, do the following:

1. Create a subnet in the target availability zone for the hosts.

2. Add a host to the cluster: in the management console, select a folder.

3. Navigate to Yandex StoreDoc.

4. Locate the Yandex StoreDoc cluster you need in the list, click its name, and select the Hosts tab.

5. Click  Create host.

6. Specify the following host settings:

   • Target availability zone for your hosts.
   • New subnet.
   • To make the host accessible from outside Yandex Cloud, select Public access.

7. Click Save.

8. Delete the hosts in the source availability zone.

Risk of data loss and cluster unavailability in the event of a zone failureRisk of data loss and cluster unavailability in the event of a zone failure

Description

The current distribution of cluster hosts does not ensure fault protection in a single availability zone. Distribute replicas across different zones to ensure high availability.

Action

To add a host to a different zone:

1. Navigate to Yandex StoreDoc.
2. Select the cluster and open the Hosts tab.
3. Click Create host.
4. In the host settings, specify an alternative availability zone.
5. Finish configuring the host and click Save.

Risk of cluster unavailabilityRisk of cluster unavailability

Description

Your host is critically low on free space. Some operations may be disabled, while the whole cluster may become unavailable, i.e., switch to read-only mode. Increase the disk size or clear unused data.

Action

To increase the disk size:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. Under Storage, increase the disk size.
4. Click Save changes.

Not enough RAMNot enough RAM

Description

The cluster is running out of RAM, which leads to slow performance or emergency shutdowns. Increase the cluster's RAM.

Action

To increase the amount of RAM:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. Under Resources, select a host class with the required amount of RAM.
4. Click Save changes.

Database version is out of dateDatabase version is out of date

Description

The database version is out of date. Support for the version was officially discontinued. Clusters are running, but support is limited. We recommend upgrading to a supported version.

Action

To upgrade the database version:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. In the Version field, select Yandex StoreDoc.
4. Click Save changes.

Risk of data lossRisk of data loss

Description

The host has a high replication lag, which may result in data loss. Check the load on the master node and replicas and optimize your requests or increase the cluster's computing resources.

Action

To increase the cluster's computing resources:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. Under Resources, select a host class with the required amount of vCPUs.
4. Click Save changes.

Disk space autoscaling is limitedDisk space autoscaling is limited

Description

The disk autoscaling limit has been reached, so the cluster cannot increase its disk space when needed. Change the autoscaling settings in the cluster and increase the limit.

Action

To increase the disk size:

1. Navigate to Yandex StoreDoc.
2. Select your cluster and click Edit.
3. Specify the maximum storage size after the expansion in the Maximum storage size field.
4. Click Save changes.