Percona-Server-shared-51 breaks MySQL on CentOS 6.6

I am not sure if I should post this here or in the Xtrabackup forum - but the problem seems related to Percona-Server-Shared-51 package.

We have a set of minimal install CentOS 6.6 servers with MySQL 5.1.73-rel14 (the default for CentOS 6) installed.

We use xtrabackup from Percona, installed via yum from the persona-release.repo. This is the only non-CentOS repo we use.

This morning, I came to do a regular round of package updates:

yum update
–> Running transaction check
—> Package Percona-Server-shared-51.x86_64 0:5.1.73-rel14.12.624.rhel6 will be obsoleting
—> Package dhclient.x86_64 12:4.1.1-43.P1.el6.centos will be updated
—> Package dhclient.x86_64 12:4.1.1-43.P1.el6.centos.1 will be an update
—> Package dhcp-common.x86_64 12:4.1.1-43.P1.el6.centos will be updated
—> Package dhcp-common.x86_64 12:4.1.1-43.P1.el6.centos.1 will be an update
—> Package kernel.x86_64 0:2.6.32-504.8.1.el6 will be installed
—> Package kernel-firmware.noarch 0:2.6.32-504.3.3.el6 will be updated
—> Package kernel-firmware.noarch 0:2.6.32-504.8.1.el6 will be an update
—> Package mysql-libs.x86_64 0:5.1.73-3.el6_5 will be obsoleted

I said ‘y’ to this on the first server. Yum went ahead, and promptly broke MySQL. Both client and server were broken. An attempt to use the client resulted in:

mysql: relocation error: mysql: symbol strmov, version libmysqlclient_16 not defined in file libmysqlclient.so.16 with link time reference

To fix this, I had to disable the Percona repo, and remove the Persona-Server-Shared-51 package. The latter also removed mysql and mysql-server packages on the way - and when I reinstalled those, they overwrote /etc/my.cnf (my fault for not anticipating this I guess). So that was a bit of fun.

Anyway - I have a few more of these slaves to update, and they’re all suggesting they’re going to ‘obsolete’ the Persona-Server-Shared-51 package also - so how do I get round this?

Also - this seems to suggest that by installing just xtrabackup from the repo, our core MySQL installation may have been modified?

PS - a thread discusses something like this happening back in 2012: http://www.percona.com/forums/questions-discussions/percona-xtrabackup/8453-yum-update-upgrade-breaks-mysql-with-percona-server-shared-and-deletes-my-cnf

However - this set of servers are all new - they were only configured a couple of weeks ago from CentOS 6.6 minimal install ISOs. It seems odd that this issue is still happening now.

PPS - After installing mysql via RPM, we originally installed xtrabackup using:

yum -y install percona-xtrabackup