When booting a VM recently, I received the error message below regarding I/O writecaching & virtual hard disk corruption:
After Googling for a bit, I found that the first thing to check with this error is whether I/O write caching is enabled on the VM. In my case, it was.
Next, a lot of the posts I was reading were stating the corruption was occuring on ext4 partitions. I assumed that the write caching was a filesystem option. I had heard of the disk write cache when working on Windows servers, but never really knew the specifics.
After a bit more research, I found disk write-caching was actually a drive option that could be set with the hdparm command. It will improve performance by 10-20%, but can also cause system instability.
To enable write-caching on the drive, I ran command:
[user@box ~]$ sudo hdparm -W1 /dev/sda Password: /dev/sda: setting drive write-caching to 1 (on) write-caching = 1 (on)
And rebooted the machine, effectively taking care of the error.