10-28-2013 01:53 AM
Hi,
I created a RAID-1 configuration on a diskgroup with two disks.
Solved! Go to Solution.
10-28-2013 04:44 AM
As mentioned in the first paragraph of the original reply:
Failure is detected automatically - DMP probes disk paths periodically to check their status, and if it detects they are offline / doesn't get a response within the defined timeframe it will fault the path (or disk if all paths have gone offline); to speed up the process you can send i/o to the disk so it will detect the failure sooner (as you've done by writing to the volume).
EDIT: further reading that may help
DMP 5.1SP1 (Linux) Administrator's Guide -> About the event source daemon
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/dmp_admin/ch06s01.htm
-> Fabric Monitoring and proactive error detection (note "previous releases" refers to pre-5.0 installs)
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/dmp_admin/ch06s02.htm
VxVM Administrator's Guide -> Performance monitoring and tuning -> Tuning VxVM -> DMP Tunable Parameters:
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/vxvm_admin/ch15s04s05.htm
(eg: dmp_monitor_fabric, dmp_monitor_osevent)
10-28-2013 03:17 AM
Failure is detected automatically - DMP probes disk paths periodically to check their status, and if it detects they are offline / doesn't get a response within the defined timeframe it will fault the path (or disk if all paths have gone offline); to speed up the process you can send i/o to the disk so it will detect the failure sooner (as you've done by writing to the volume).
Once you replace the disk (or enable the disk in this case); VxVM will detect the disk has been repaired/replaced - this can be automatic eg: if vxesd is running, or you may need to do this with vxdisk scandisks - check by running vxdisk list after the scandisks and the repaired disk should be listed with online status.
The recovery of the mirror plexes is not automatic, as the disk could have been replaced with a new device, so you need to perform additional steps after vxdisk scandisks has been run to detect the disk is back/online to recover the volumes.
eg: vxreattach to reattach disk drives that have once again become accessible (your case above)
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/manualpages/html/manpages/volume_manager/html/man1m/vxreattach.1m.html
(vxreattach -c {accessname} to check if the device can be reattached, then vxreattach -r {accessname} to recover)
see also: vxdiskadm for failed/replaced disks (ie: where the disk has physically been replaced with another device)
VxVM 5.1SP1 (Linux) Administrator's Guide -> Administering Disks -> Removing and replacing disks -> Replacing a failed or removed disk
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/vxvm_admin/ch03s19s01.htm
see https://sort.symantec.com/documents and select the relevant platform/version combination if your versions differ / you need more details.
10-28-2013 04:13 AM
Thanks for the reply.
My requirement was to reattach the mirror plex automatically, once the underlying disk comes back.
But looks like for mirror plexes, it is not automatic and some manual intervention is required. I can monitor the disk and once the disk comes back I can reattach it.
Another point which I mentioned above, once the underlying disk is becoming unavailable, the corresponding plex is not getting disabled unless I do some IO operation on the volume. Is that expected behavior?
Regards,
Hari.
10-28-2013 04:44 AM
As mentioned in the first paragraph of the original reply:
Failure is detected automatically - DMP probes disk paths periodically to check their status, and if it detects they are offline / doesn't get a response within the defined timeframe it will fault the path (or disk if all paths have gone offline); to speed up the process you can send i/o to the disk so it will detect the failure sooner (as you've done by writing to the volume).
EDIT: further reading that may help
DMP 5.1SP1 (Linux) Administrator's Guide -> About the event source daemon
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/dmp_admin/ch06s01.htm
-> Fabric Monitoring and proactive error detection (note "previous releases" refers to pre-5.0 installs)
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/dmp_admin/ch06s02.htm
VxVM Administrator's Guide -> Performance monitoring and tuning -> Tuning VxVM -> DMP Tunable Parameters:
https://sort.symantec.com/public/documents/sfha/5.1sp1/linux/productguides/html/vxvm_admin/ch15s04s05.htm
(eg: dmp_monitor_fabric, dmp_monitor_osevent)