FAQs

When taking leaves nodes offline without cluster downtime:

1. What happens if an ingestion is in progress?

It will fail on the leaf that went offline, and get retried on the leaf to which the faileover occurred.

2. How can you be sure that the data will be consistent when a leaf node fails over?

Data will be consistent in synchronous replication. No transactions get committed until they have been replicated.

3. Do you need to pause the replication for stopping a leaf node, child aggregator, or master aggregator?

No, it’s not even possible to do so.

4. Does synchronous/asynchronous replication make any difference in this process?

Yes, asynchronous replication is not recommended. Synchronous replication provides stronger data consistency.

5. When performing a rolling restart of multiple leaf nodes, do you need to rebalance after restarting each leaf node?

No, it is not required.

6. How does a long running query or a running backup impact this operation?

The failover will not be blocked. However the long running queries or backups will fail when the failover happens.

Last modified: June 22, 2022

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Verification instructions

Note: You must install cosign to verify the authenticity of the SingleStore file.

Use the following steps to verify the authenticity of singlestoredb-server, singlestoredb-toolbox, singlestoredb-studio, and singlestore-client SingleStore files that have been downloaded.

You may perform the following steps on any computer that can run cosign, such as the main deployment host of the cluster.

(Optional) Run the following command to view the associated signature files.
Shell
```
curl undefined
```
Download the signature file from the SingleStore release server.
- Option 1: Click the Download Signature button next to the SingleStore file.
- Option 2: Copy and paste the following URL into the address bar of your browser and save the signature file.
- Option 3: Run the following command to download the signature file.
  Shell
```
curl -O undefined
```

After the signature file has been downloaded, run the following command to verify the authenticity of the SingleStore file.

Shell

echo -n undefined |
    cosign verify-blob --certificate-oidc-issuer https://oidc.eks.us-east-1.amazonaws.com/id/CCDCDBA1379A5596AB5B2E46DCA385BC \
      --certificate-identity https://kubernetes.io/namespaces/freya-production/serviceaccounts/job-worker \
      --bundle undefined \
      --new-bundle-format -

Verified OK