I have a failed drive on a dell poweredge 2650. new drive is on the way. is it better to just turn off the server over the weekend till the new drive gets here to avoid any chance of at catastrophic second drive failure, or leave it on?
That there is one of those problematic manager calls. How critical is it that the server be accessible over the weekend? How much effort will it take to restore data and rebuild the array if the other drive is lost. Where is the balance between the two? Create a backup and run it I will say with the reasoning that if the other drive fails, you would need to wait that much longer to restore and rebuild the array anyway (unless you're ordering a few HDD's now)
If the server is not playing a critical role here, it's a no-brainer... shut it down and wait (it may save headaches later)