Extended support
From Atomicorp Wiki
Extended Support Contracts
Centos 5
Support is not available for Centos 5 after March 31, 2017.
Redhat 5
Customers must have an Extended Life-cycle Support (ELS) add-on subscription from Redhat. RHEL5 systems without ELS add-on subscriptions from Redhat are not supported.
Customers may purchase annual an Extended Support Contract (ESC) to support Redhat 5's that are EOL as of March 31, 2017. Contact sales for details.