Plesk 9.5.4 supports PHP version 5.2.17 and optionally you can add PHP 5.3 support.
PHP 5.3 can be enabled in Home > Help Support > Updates section. But this version isn’t latest one. So we need to upgrade PHP manually.
Default Centos repository does not allow php to latest so I use another repository (atomic/remi)
To enable atomic use command below.
wget -q -O - http://www.atomicorp.com/installers/atomic | sh
Now you can test upgrading PHP with yum but plesk wont let you do this.
You can read kb article of parallels to upgrade.
After upgrade you may have mysql problem. You can see error log below:
110802 9:42:40 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it. 110802 9:42:40 InnoDB: Initializing buffer pool, size = 2.0M 110802 9:42:40 InnoDB: Completed initialization of buffer pool 110802 9:42:40 InnoDB: Started; log sequence number 0 1023798 110802 9:42:40 [ERROR] /usr/libexec/mysqld: unknown option '--skip-bdb' 110802 9:42:40 [ERROR] Aborting
To fix this delete or comment skip-bdb line in /etc/my.cnf file. Then you can start mysql service.
And you have to run following otherwise yo get “ Error: Connection to the database server has failed:Table ‘mysql.servers’ doesn’t exist” error when creating database through plesk panel.
mysql_upgrade --user=admin --password=PLESK_PASS --verbose
After all this you can use latest version of php and plesk 9.5.4
Parallels does not support this upgrade and I will not take any responsibility for problems after upgrading PHP.