NTBackup byte estimate very slow, can't find C:\
Posted on 2008-09-30
We've been using NTBackup for quite some time now to do a nightly backup of one of our servers. It has been working without any issues for over a year now but suddendly at the end of last month it began not to work and has not worked since.
What is happening is when the backup job runs, the "Selection Information" screen appears with the File and Byte Estimate information, this takes an abnormally long time to complete...in fact I have only seen it complete once after letting it run for almost two weeks (keep in mind the backup, when it did work prior to this issue, was only about 18 GB). When it finally did complete the estimation, I don't remember the exact text but it returned an error saying it could not find or have permission to C:\ (the job is set to backup C:\ and System State) and the backup failed.
Running the job manually yields the same result Selection Information screen appears and takes an abnormal time to calculate, if I click cancel here NTBackup hangs. There reports NTBackup creates are blank so they don't offer much assistance and there seems to be nothing in the event log other than an entry showing that NTBackup operation started on C:\ but there is nothing showing it finished or errored out, etc. (unless I cancel the job, then it will show an Application Hang entry)
Operating system is Windows Server 2003 Enterprise Edition SP2, NTBackup is backing up to a SNAP2200 NAS device (but the same thing happens even if I back up to anoter local hard disk). I have been scouring the web and even looked at some Partner level KB articles for the same problem, and while I have tried solutions used on similar issues, nothing has yet to yield success.
I have attempted the following:
-Update NTBackup build with hotfixes provided by Microsoft, currently running build 5.2.3790.4166 of NTBackup
-Delete and recreate backup job
-Recreate .bkf file that job backs up to
-Re-register VSS Writers with the following procedure:
CD to Windows\System32
Net stop vss
Net stop swprv
regsvr32 /i swprv.dll
regsvr32 /i eventcls.dll
I hope I provided sufficient detail here, if not please let me know and I will try to provide any information I can.