pt-table-checksum in master-master environments

Asked by Volans on 2012-02-07

I would like to know if it is safe (from the replication point of view) to run pt-table-checksum toolkit in environments with a master-master MySQL configuration with slaves like this one:

A=B
 | |
C D

Masters:
* A is slave of B
* B is slave of A

Slaves:
* C is slave of A
* D is slave of B

The documentation do not discuss about such a configuration, unlike the pt-table-sync documentation for example.

In addition to the safety of the tool, I would like also to know if running pt-table-checksum on server A, automatically make the ckecksums on all the other servers.

Thank you in advance

Question information

Language:
English Edit question
Status:
Solved
For:
Percona Toolkit Edit question
Assignee:
No assignee Edit question
Solved by:
Volans
Solved:
2012-02-08
Last query:
2012-02-08
Last reply:
2012-02-07
Baron Schwartz (baron-xaprb) said : #1

It is like any other application that writes data to the database. For example, you shouldn't run it on the passive master.

Yes, the checksums will flow through replication like any other updates.

There is nothing exotic about what it does -- it is just running statements like any other application.

Volans (volans) said : #2

I agree with your reply, just wondering why are you referring to a "passive master".

The configuration I have explained is an active-active master-master replication where both A and B are active masters. The same arguments can be applied also in this case?

Thank you for your really quick reply.

Baron Schwartz (baron-xaprb) said : #3

I apologize for changing direction on this, but would you please post your question on http://forum.percona.com instead? I have reconfigured Launchpad to not offer the "answers" feature because it is not manageable for us to maintain forums in a lot of different places online. It was only enabled because that's the Launchpad default and we never disabled it.

Volans (volans) said : #4

Ok, no problem, I have created this topic, hoping to have opened it in the right section:

http://forum.percona.com/index.php?t=msg&th=2084&start=0

Thanks for your support here.