udunmirror errors

Message text

udunmirror: i/o error on primary device '%s'
udunmirror: i/o error on secondary device '%s'
udunmirror: failing over to '%s'

Explanation

This error occurs when Adaptive Server detects an I/O error on the primary or secondary device of a mirrored pair of devices. It is usually the result of a physical disk problem.

If an I/O error is detected on the primary device, Adaptive Server disables mirroring. sysdevices reflects information for the device as if a disk unmirror with side = primary and mode = retain was issued. Adaptive Server does this automatically and writes kernel messages like the following to the error log:

kernel: udunmirror: i/o error on primary device '<primary_device>'
kernel: DataServer i/o to the device will be disabled
kernel: udunmirror: failing over to 'secondary_device''

If an I/O error is detected on the secondary device, Adaptive Server disables mirroring and sysdevices reflects information for the device as if a disk unmirror with side = secondary and mode = retain was issued. Adaptive Server does this automatically and writes kernel messages like the following to the error log:

kernel: udunmirror: i/o error on secondary device  '/usr/u/sybase/test.mir'
kernel: DataServer i/o to the device will be disabled

Action

1. Using your operating system procedures, determine whether the device is damaged. If it is damaged, repair or replace it.

   If the device is not damaged but it was unavailable for some other reason, make it available again.

2. If you use operating system files for Sybase devices or if the name of the device was changed, drop the mirror and re-create it:

   1> disk unmirror name = "<device_name>",
   2> side = {primary|secondary}, mode=remove
   3> go
   

   1> disk mirror name = "<device_name>",
   2> mirror = "<full_mirror_name>"
   3> go
   

   Where side is the device that was temporarily disabled.

   On a UNIX system, you can also use the operating system command touch to create the file, then issue a disk remirror command.

3. If you did not need to drop and re-create the mirror, use the disk remirror command to make the device accessible to Adaptive Server:

   1> disk remirror name = "<device_name>"
   2> go
   

   Use the disk remirror command if Adaptive Server automatically disabled mirroring, or if you issued a disk unmirror with mode = retain command. If you issued a disk unmirror with mode = remove command, you can only reinstate disk mirroring by issuing the disk mirror command.

Additional information

Refer to the Reference Manual: Commands for information about using the disk mirror, disk remirror, and disk unmirror commands.