Symantec Veritas Cluster Server One, Installation Manual

Page: 152 / 210

152 Troubleshooting
Troubleshooting I/O fencing
Troubleshooting I/O fencing
This section provides solutions to the following I/O fencing issues:
■
“ vxfentsthdw fails when the SCSI TEST UNIT READY command fails ” on
page 152
■
“ vxfentsthdw fails when prior registration key exists on disk ” on page 152
■
“ System panics to prevent potential data corruption ” on page 153
■
“ Using the vxfenclearpre command to clear keys after split brain ” on
page 155
■
“ Adding or removing coordinator disks ” on page 156
■
“ How I/O fencing works in different situations ” on page 158
vxfentsthdw fails when the SCSI TEST UNIT READY command fails
If you see a message resembling:
Issuing SCSI TEST UNIT READY to disk reserved by other node
FAILED.
Contact the storage provider to have the hardware configuration
fixed.
The disk array does not support returning success for a SCSI TEST UNIT READY
command when another host has the disk reserved using SCSI-3 persistent
reservations.
vxfentsthdw fails when prior registration key exists on disk
Although the situation is unlikely, you may try to use the
vxfentsthdw
utility
to test a disk that has a registration key already set. If you suspect a key exists
on the disk you plan to test, use the
vxfenadm -g
command to display the key.
vxfenadm -g diskname
■ If the disk is not SCSI-3 compliant, the following error is returned:
Inappropriate ioctl for device
.
■ If you have a SCSI-3 compliant disk and no key exists, the output resembles
the following:
Reading SCSI Registration Keys...
Device Name: diskname
Total Number Of Keys: 0
No keys ...
Next, test the disk using the
vxfentsthdw
utility.
See “ Setting up and testing data disks ” on page 79.
■ If keys exist, you must remove them before you test the disk.
See “ System panics to prevent potential data corruption ” on page 153.