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System error 121 (The semaphore timeout period has expired)

russellfoggyrussellfoggy Posts: 10
edited July 21, 2009 10:31AM in SQL Backup Previous Versions

We created a new backup job on a newly redployed server last night and the backup failed with the error below, I have searched the support site but cannot find a reference to the error

SQL backup 5.3
SQL 2005

7/19/2009 11:36:31 PM: Thread 0 error:
Error 620: Error writing to backup file(s).
Process terminated unexpectedly. Error code: -2139684860
7/19/2009 11:36:31 PM: Warning 210: Thread 0 warning:
Warning 210: Error writing to backup file: \\jhbh-srv-red01\SQL BACKUPS\JHBH-SRV-MER01\FULL_(local)_MERLIN_HO_20090719_233005.sqb
Warning: System error 121 (The semaphore timeout period has expired)



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    Eddie DEddie D Posts: 1,793 Rose Gold 5
    Thank you for your post into the forum.

    This part of the error message: Warning: System error 121 (The semaphore timeout period has expired), indicates a network error or problem occured during the backup process. So the connection was lost to the network share.

    This could be a connectivity issue where:
      Network adapters and switch ports have mismatching duplex levels or transfer speed settings. Network adapters or switches with transmission rates of 10/100 megabits per second (Mbps) do not switch over correctly. Some autosense settings may not correctly detect the speed of some network adapters. The network adapter is incompatible with the motherboard or other hardware or software components and drivers.

    Another possible cause is that the server performing the backup did not enough free resources or was busy and could not respond to the semaphore before timing out.

    Another possible cause is that the amount of data placed onto the network that SQL Backup outputs onto the network. SQL Backup writes out the compressed data in blocks of 4MB by default. Unfortunately, on some networks this fails.

    To get around this issue the user must specify the MAXDATABLOCK option, to specify the maximum size of data blocks to be used for writing data to network shares. Valid values are integers in multiples of 65536 up to a maximum value of 4194304. If you edit the scheduled job, on Step 5 of the 'Schedule Backup Wizard' you can specify the MAXDATABLOCK value.

    I hope the above helps.

    Many Thanks
    Eddie Davis
    Senior Product Support Engineer
    Redgate Software Ltd
    Email: support@red-gate.com
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