error in mounting file system

[Fadia Almarei]

I have error in one of my HP-UX 11.23 server with rx6600 , we get problem in mounting one of our mount points with the following error, kindly note that this server is a production server and we need to solve the problem as soon as possible

# mount -F vxfs /dev/vgarch/lvarch /arch01

UX:vxfs mount: ERROR: V-3-20005: read of super-block on /dev/vgarch/lvarch failed: I/O error

UX:vxfs mount: ERROR: V-3-24996: Unable to get disk layout version

Kindly your help to solve the problem and keeping the data .

# vgdisplay -v vgarch

vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c1t4d0":

The specified path does not correspond to physical volume attached to

this volume group

vgdisplay: Warning: couldn't query all of the physical volumes.

--- Volume groups ---

VG Name                     /dev/vgarch

VG Write Access             read/write

VG Status                   available

Max LV                      255

Cur LV                      1

Open LV                     1

Max PV                      16

Cur PV                      2

Act PV                      1

Max PE per PV               65535

VGDA                        2

PE Size (Mbytes)            16

Total PE                    8749

Alloc PE                    8749

Free PE                     0

Total PVG                   0

Total Spare PVs             0

Total Spare PVs in use      0

vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c1t4d0":

The specified path does not correspond to physical volume attached to

this volume group

vgdisplay: Warning: couldn't query all of the physical volumes.

   --- Logical volumes ---

   LV Name                     /dev/vgarch/lvarch

   LV Status                   available/syncd

   LV Size (Mbytes)            279968

   Current LE                  17498

   Allocated PE                17498

   Used PV                     1

   --- Physical volumes ---

   PV Name                     /dev/dsk/c1t5d0

vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c1t4d0":

The specified path does not correspond to physical volume attached to

this volume group

vgdisplay: Warning: couldn't query all of the physical volumes.

   PV Status                   available

   Total PE                    8749

   Free PE                     0

   Autoswitch                  On

   Proactive Polling           On

[Patrick Wallek]

It appears that one of the disks, /dev/dsk/c1t4d0, in  your VG is dead.  

If the /dev/vgarch/lvarch spans both disks in the VG,c1t4d0 and c1t5d0,  and was not mirrored, then the dead disk is the reason your LV is not mounting.

Do an 'lvdisplay -v /dev/vgarch/lvarch' and post the first 25 - 30 lines of the output.