Microsoft Windows SBS 2008 backup fails with "incorrect function" on punctured RAID array

PaulNicodemi used Ask the Experts™
Hello, all,

I am running SBS 2008 and have been using the integrated backup software without incident for the life of the server.  At one point the backups were failing, which, after research, led me to notice that they had one failed RAID drive, and another in predicted fail.  Replaced both drives (one by one) without incident and am now showing a healthy array.

Dell Poweredge server
RAID-5 array with three (3) physical disks
No other RAID arrays on the system

However, backups still continue to fail with the dreaded "incorrect function" error message.  They always fail at exactly the same spot on the c: drive, 49.31 MB into the backup, and the entire backup aborts.  Reviewing the application log doesn't yield anything helpful, but reviewing the system log shows an error message the recurs every few hours about a punctured RAID array, and specifically calls out physical disk 1.  Strangely, physical disk 1 is the only disk of the three that I DID NOT replace.  However, I know bad parity can copy from one disk to another in a double-fault situation.

I am aware that the only way to truly repair a punctured RAID is to completely reinitialize the RAID array and start from scratch.  However, the puncture is not affecting anything on the server, and it's running fine since I replaced the disks.  Reformatting would be an insurmountable task at this point, and is not an option, nor is it necessary as the server is running fine.

So my question is this:

1) Is the puncture causing the backups to fail, or should I be looking elsewhere? I mean, Is it possible that SBS backups are so FRAGILE that they completely abort because of a simple bad block or RAID puncture?
2) If the puncture is at fault, how can I tweak the backups so that they complete despite the puncture.
3) If it's not at fault, how can I correct the "incorrect function" error?

I am willing to post event logs or provide any other information that you deem vital to the situation.  Thanks in advance for the help!
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Top Expert 2016

if you can't reformat and restore from backup why are you even running backups?
Most Valuable Expert 2015
Open an elevated CMD prompt and run chkdsk c: /f /r (do that for the other drive letters too). The server will have to do this while booting and it can take some time depending on how large the array is and the number of file-system problems it finds and repairs, so do this while the server isn't being accessed.

After that try backing up again. Very often backups fail because of file-system corruptions.
IT Product Manager
Top Expert 2009
Though you have resolved the problem with RAID it remained in file system. Thus you need to clean up the file system of C and other drives. Run as noted above check via CHKDSK c: /r and let it perform the scan at reboot. Then retry the backup.
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David: Backups have been failing for so long now that they are not a viable recovery option; they're over 2 months out of date at this point.

Rindi/noxcho:  I'll try running a chkdsk on the server and let you know what it turns up.



I ran a chkdsk on the c: drive during the after-hours using the startup scan.  Ran a test backup afterwards and it completed on C: for the first time since the drive issues, but then hung up on D: with an incorrect function message again.  I'm hoping a similar scan on the D: partition fixes that failure as well.  I'll try this again tonight and let you know.  Thanks!
noxchoIT Product Manager
Top Expert 2009

Yes, and if you have more partitions on that drive - scan all of them.

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