0

I have 3 nodes PXC 5.6 cluster. Xtrabackup 2.3.10. Centos 7.6

Percona-XtraDB-Cluster-56-5.6.41-28.28.1.el7.x86_64

I am using only single Node-1 for both read and write.

And I use to take backup from another Node-2 which is not used for read or write.

Yesterday, my Node-1 went down and read/write switched to Node-2. Then we continued to take incremental backup from another unused Node-3.

On my backup machine, I decided to extract and prepare backup. My backup preparation log shows everything fine until those backups that were taken from Node-2. All the incremental backups from Node-3 had errors.

Why does it seems like incremental backup should always be from the same node where the full backup was taken? Percona XtraDB Cluster is master-master and so all nodes must be same. Then why did this happen?

I have attached my logs here:

https://www.percona.com/forums/questions-discussions/percona-xtradb-cluster/53285-xtrabackup-corrupts-incremental-backup-when-node-changes

0

LSN (Log Sequence Number), which incremental backup is based on, is specific to an instance. That's why knowing full copy LSN means nothing on other node.

  • What is the solution to solve this problem? I want to automate this process so if a node goes down, incremental backups should be normal and not corrupt. – Jaz Jan 13 at 14:18
  • When you switch a backup node start with a full copy. I also found differential backup are more reliable comparing to incremental. I implemented both aspects in github.com/twindb/backup. Also it correctly desyncs a node before the backup which is important for Galera Cluster backups. – akuzminsky Jan 13 at 15:02

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.