I wouldn't say it's straightforward. It depends on how risk-tolerant you are. At a minimum, the mysql_upgrade process needs to happen. I believe that if the data is important, using pt-upgrade to validate that everything still works as expected afterwards is also pretty much a minimal requirement for such a big upgrade.

The MySQL manual's upgrading pages for each major version, and the changelogs between those versions, are important to read too.

Thanks, I got the upgrade done.

1. Backup (of course)
2. Stopped old server.
3. Uninstalled it (yum remove)
4. Installed Percona mysql through RPM
5. Addressed any library conflicts (had to remove additional 5.0 libraries)
6. Updated configuration file to remove incompatible settings
7. Started new mysql
8. Run mysql_upgrade

Things are looking good.

One of the things I try to make everyone aware of when upgrading from 5.0 -> 5.1+ is the change in some of the charset/collations that happened in 5.1.24

In specific this changelog.

Incompatible Change: The utf8_general_ci and ucs2_general_ci collations did not sort the letter "U+00DF SHARP S" equal to 's'.

As a result of this bug fix, indexes must be rebuilt for columns that use the utf8_general_ci or ucs2_general_ci collation for columns that contain SHARP S. See Section 2.13.3, "Checking Whether Tables or Indexes Must Be Rebuilt". (Bug #27877)


Ensure you understand what this means and whether or not you want to use these charsets or whether you want to use the Percona compatible ones.

This percona blog post mentions the compatibility patches introduced in 5.1.58 by percona:

http://www.mysqlperformanceblog.com/2011/08/17/percona-serve r-5-1-58-12-9/