We are going to perform emergency drive replacement on the Olga server. This is a RAID machine with hot swap drive so it should remain online as the drive is replaced. Once the new drive has been installed and all data has been replicated we will do the same thing with the secondary drive in the RAID array so that the end result is two brand new hard drives.
This machine has been in and out of Read-Only modes and though all disk diagnostics state that the drives are fine, experience is telling us otherwise and it is likely time to get some new drives installed on this unit.
We hope this will solve the issues with exim and MySQL which are located in the /var partition and this is the partition that is most frequently set to read only by the OS.
We do not anticipate any downtime but as with any maintenance there is always that possibility so we will keep you posted if there is, and rest assured we know about it long before you post here or in a trouble ticket and we will be working fast and furious to get things back to normal.