How risky is it to use unsupported MySQL (5.1)?

Question

I administer a Confluence Server instance, but our infrastructure is managed by a different department – we installed Confluence 5.6 fresh on CentOS 6 using the built-in MySQL 5.1 package, and I updated shortly after to Confluence 5.7 without realizing that version dropped support for MySQL 5.1.

So far everything's been working fine, but I'm very adamant about keeping our Confluence up-to-date with new releases and our MySQL is probably going to be tracking the CentOS distribution. So how dumb would it be for me to try to continue upgrading Confluence from this point? Only a little dumb? Massively stupid?

(Also realizing now that CentOS 7 doesn't actually include MySQL anymore, and MySQL itself doesn't support 5.1 running on CentOS 6... so maybe there's hope for getting us off the included package after all. Anyway, still curious about the above question.)

Nic Brough -Adaptavist- · Answer

I'd say it's a very low risk.  In most cases, using a "slightly behind the version we support" database is not going to cause many problems because the later versions tend to be mostly backward compatible.

Unless the application is deliberately using some wonderful new feature (Very unlikely in something like JIRA which can use several databases and hence tends not to use the clever stuff in any one particular database), or there's some bug or feature that specifically breaks something in the application, you probably won't have any issues with it.

Of course, the risk of a break increases exponentially as you move further away from the supported versions.  But most important is the point Eduardo makes - if you do run into a problem and ask for support, the only response that you're entitled to is "move to a supported configuration and try again".

Being entitled to a response and what you tend to get from Atlassian support are not the same though.   I've run JIRA on totally unsupported setups, run into problems, asked for help from Atlassian and they've done their absolute best to fix it without having to force me on to supported configs.  It's good support.  But they always have the fall-back of asking you to move within the parameters that they officially support.  So get on to 5.5 as soon as you can!

(As a personal aside, I'd like to see the list of databases extended to include Maria and the transactionally safe NoSQL implementations, but, we all have dreams...)

Mallmann · Answer

Hello Nick,

I wouldn't say you are dumb or anything like that at all for using an unsupported version. You just need to bear in mind that you might face incompatibility issues when upgrading or installing some plugin or something like that if you still use unsupported database version.

Also, in case you face outages on your instance for example, first thing our support would ask would probably be related to getting your database to a supported version since we cannot guarantee that the instance runs smoothly if you're not running it in a supported environment.

I'd also recommend you to keep an eye on this KB: https://confluence.atlassian.com/display/CONFKB/Known+Issues+for+MySQL

Lastly, as long as you always keep backups from your instance so you can rollback in any pretty complicated issue you run, you should be safe to go.

In my personal opinion, I think you should work on getting the database updated as soon as possible to avoid further issues

I hope it helps!

Eduardo