Advice regarding Database migration

[Andrew Nisbet]

I need to migrate our production system from Postgresql to MySQL.

My thought is to:

1. back up the App

2. Spin up a raw copy of Jira backed by MySQL

3. Restore the APP from the XML file

4. Roll over DNS, ETC.

5. bring down old instance

Should be strait forward, but I am a little worried about the back-up XML file not restoring correctly. Does anyone have advice on things I should be careful of?

Thanks

[Ivan Tse · Accepted solution]

Hey Andrew,

In many cases we actually recommend using the XML restore method. I haven't seen significant issues with it before unless the database created in mysql isn't set to what JIRA expects. From what you described, it sounds more like you're moving servers completely rather than just databases.

If you're going to just move databases, you should be able to just spin JIRA down, reconfigure it to point to the mysql database then restore the backup zip. Your postgres server at this point won't be touched so the data there will stay as is.

Other than that, before doing anything I recommend backuping everything up.

[Andrew Nisbet]

Thanks for the replys everyone. Going to give it a go tomorrow.

[Norman Abramovitz]

Do not forget to backup the attachments as well.

https://confluence.atlassian.com/display/JIRA051/Restoring+Data

https://confluence.atlassian.com/display/JIRA051/Restoring+Data#RestoringData-3.Restoringattachments

[Davet]

As Harry says "give it more RAM" or your XML backup will likely fail.

Also you may want to pay some attention to db settings like "CHARACTER SET utf8 COLLATE utf8_bin;" and to your "my.cnf" depending on the size and activity of the db.

Notably

default-storage-engine=INNODB

transaction-isolation=READ-COMMITTED

innodb_log_file_size=default is way too small

slow_query_log=1 (possibly)

[Harry Chan]

Hi Andrew, this would depend on the size of your instance. XML backups eat ram. If you do have huge instances it'd fail and/or take a very long time.