I would wait for a rebuild before touching the firmware After the rebuild do a backup as soon as possible. Depending on the drive size it may take some time for it rebuild. Running a degraged set will make the server run a lot slower and another drive failure will cause an unrecoverable RAID failure.
I would also get imaging software such as Symantec Backup Exec System Recovery or Altiris which allow you to image the server and if it crashes restore in a very short time from bare metal, no OS re-install required.