I tried to update MySQL from 5.1 to 5.5 in CentOS 6.2. The following is the process I did:
1. rpm -Uvh http://repo.webtatic.com/yum/centos/5/latest.rpm 2. yu
I used the following commands to add a new YUM repo and make the update:
Download the Remi repo
cd /etc/yum.repos.d wget http://rpms.famillecollet.com/enterprise/remi.repo
Install/Update the mysql version
yum --enablerepo=remi install mysql-server
OR
yum --enablerepo=remi update mysql-server