HP-UX Operating Systems - Error Messages in Syslog.log; Fibre Cable Connected to Server Is Bad

HP-UX Operating Systems - Error Messages in Syslog.log; Fiber Cable Connected to server Is Bad

ISSUE:
The following error messages are in the syslog.log :
Jun 5 15:09:25 vmunix: LVM: WARNING: VG 64 0x010000: LV 10: Some I/O requests to this LV are waiting
Jun 5 15:09:25 vmunix: indefinitely for an unavailable PV. These requests will be queued until
Jun 5 15:09:25 vmunix: the PV becomes available (or a timeout is specified for the LV).
Jun 5 15:09:39 vmunix: LVM: NOTICE: VG 64 0x010000: LV 10: All I/O requests to this LV that were
Jun 5 15:09:39 vmunix:waiting indefinitely for an unavailable PV have now completed.
Jun 5 15:14:55 vmunix: LVM: WARNING: VG 64 0x010000: LV 27: Some I/O requests to this LV are waiting
Jun 5 15:14:55 vmunix: indefinitely for an unavailable PV. These requests will be queued until
Jun 5 15:14:55 vmunix:the PV becomes available (or a timeout is specified for the LV).
Jun 5 15:15:11 vmunix: LVM: NOTICE: VG 64 0x010000: LV 27: All I/O requests to this LV that were
Jun 5 15:15:11 vmunix:waiting indefinitely for an unavailable PV have now completed.
Jun 5 15:15:54 vmunix: LVM: WARNING: VG 64 0x010000: LV 27: Some
I/O requests to this LV are waiting
SOLUTION:
The following troubleshooting steps are taken:
1. The syslogs are checked and there are many errors.
2. The ioscan is run and everything looks fine.
3. The vgdisplay output is checked and everything looks fine.
4. The LVM patches are checked to see if the latest ones are installed.
5. The sar output is checked to see the activity of the disks, using sar -d . There is no improper behavior.
6. It appears that there might be an issue with the fiber connectivity due to the many errors around the disks.
The fcmutil commands are run to check the status of fiber connectivity for both fiber channel ports.

fcmsutil /dev/fcd0

fcmutil /dev/fcd0 stat -s

fcmsutil /dev/fcd1

fcmutil /dev/fcd1 stat –s


Analysis
(/dev/xp_vgsapPRD) #fcmsutil /dev/fcd0 stat -s Thu Jun 5 16:06:31 2008 Channel Statistics

Link Statistics from firmware ...
Link Failure count 0 Loss of Sync count 0
Loss of Signal count 0 Prim seq proto err count 0
Invalid Word count 0 Invalid CRC count 0

(/dev/xp_vgsapPRD) # fcmsutil /dev/fcd1 stat -s Thu Jun 5 16:07:11 2008 Channel Statistics
Link Statistics from firmware ...
Link Failure count 0 Loss of Sync count 0
Loss of Signal count 0 Prim seq proto err count 0
Invalid Word count 0 Invalid CRC count 9469

The invalid CRC count for /dev/fcd1 is very high.
The fiber cable connected to /dev/fcd1 is changed, and the error disappears