The most recent change we made was to replace their aging HDD’s in RAID 1 with some SSDs. It was not as easy as removing one drive and replacing it and letting the PERC card rebuild.
The reason?
You might know, or will find out if you attempt this as well, that a PERC controller card can have HDDs and SSDs attached to it, however, they cannot be in the same virtual drive. This makes sense as we all know SSDs can be 10 to 20 times faster than mechanical HDDs.
With that in mind, this is how we accomplished this task.
1. We first took a “Bare Metal” backup from the server. If you don’t already do them, I would highly recommend it. It has saved many of our clients’ butts over the years.
2. After the backup was done, we verified that it was successful by recovering the backup to another machine. When it booted successfully, we knew it was good.
3. We then booted into the PERC controller and removed the previous virtual disk. You may be able to create a new virtual disk and save the previous one “just in case”, but we opted to delete it.
4. I replaced the HDDs with SSDs in their caddies.
5. We created a new virtual drive in the PERC controller. We had to select each SSD and “enable” it for RAID.
6. After reboot the server with OS installer media attached, we chose
“repair” and then restore from backup.
7. Be prepared to wait for a while as the installer tries to locate the backup media. It took about an hour on this particular server.
8. We chose the most recent backup and clicked through the restore process.
9. After restoration and reboot, the server came back up like nothing was wrong! A few smoke tests showed it responding quite a bit faster. Old average response times on the PERC array were anywhere from 7ms to 100ms while under load. So far we are seeing 0.2ms to 3ms. I’d say that is quite a bit faster!