STATIC MIRRORING

[Rommel Cuevas]

Hello everyone, i hav a problem on making a static disk mirror of my HP-UX 11.0 server.
I have 2 38GB disk. The first disk is primary and the other is supposed to be my mirrored disk.
I've followed the procedure given by RAC to Paul perugini(posted last April 26). And I test it on my workstation and it works. The problem is when i applied the procedure to my server,i hav encountered something unusual, why is it when i ran

dd if=/dev/vg00/rlvol1 of=/dev/vg01/rlvol1 bs=1024k

it never copies the contents of the source to the destination? same results on other logical volumes. Is there something i need to change on the parameters of command?

[RAC_1]

The command is correct. what it returns when you execute it.

Also what makes you think that it is failing? Any error message?

Anil

[Francesco Campalastri]

May you also give us the output of



time dd if=/dev/vg00/rlvol1 of=/dev/vg01/rlvol1\
bs=1024k

just to see how log it happens


Francesco

[A. Clay Stephenson]

If I can assume that you are running LVM (as opposed to VxVM) then your commands should work. Of course, it is possible that the actual size of the source LVOL is zero. What does dd report that it has copied?

vgdisplay -v vg00
vgdisplay -v vg01

ls -l /dev/vg00/rlvoll
ls -l /dev/vg01/rlvol1

lvdisplay /dev/vg00/lvol1
lvdisplay /dev/vg01/lvol1

Post those outputs and some definitive answers are possible.

[A. Clay Stephenson]

I just noticed that you are copying vg00 so that you are apparently trying to make a boot disk copy. If so, forget about all this LVM stuff and deactivate the vg01 volume group and indeed vgexport it. You don't need it at all.

You need to do a raw disk copy instead.

dd if=/dev/rdsk/c0t6d0 of=/dev/rdsk/c1t5d0 bs=256k

This will copy everything assuming you are using identical disks. In order to boot, the copied disk must be set to the same address as the original and because filesystems are mounted, an fsck will be required after the machine boots on the copy.

You really should be using MirrorDisk/UX to do this because your mirrors are then always up to date and indeed your machine can continue to run with a failed disk.

[Rommel Cuevas]

HI,

RAC: Theres no error message when i execute the dd command and also theres no successful output that says
"f+p records in" , "f+p records out".
but the unusual thing is, when i tried it on my workstation it takes several minutes to copy while on my server, the moment i hit the return key, i got an immediate prompt.

TO EVERYONE: ihav attached a file that u could examine. And pls tell me were i got wrong.

Thank you 4 ur rapid immediate reply.

[Rommel Cuevas]

CLAY: Ur right! i need a duplicate copy of my disk, which i can used, if my primary disk fails.