N class internal drive replacement

[Ron DeBorde]

We have had a failure on the primary boot disk in a N class. The system is operating on the mirror at this time. The OS is HPUX 11i. At one time I thought that "Hot Swapping" the disk was not supported, but I am not sure now. Is it replaceable without shutting down the system? I know there are certain things that need to be done to the disk after replacement and if it can be replaced "online" so to speak that would be very helpful. Thanks, RD

[Jeff Schussele · Accepted solution]

Hi Ron,

Although N-class drives are not "optimized" for hot swapping - it can be done. I've performed swaps several times. You'll get on lbolt message when it's pulled & recabled but those or more informational than anything.
One thing I would caution is that IF there's any other devices on the same bus as the failed drive, make sure they're quiesced when you do this.

HTH,
Jeff

[Stefan Stechemesser]

Hi Ron,

the N-Class internal disks are "hot plug" disk. In contrast to "hot swap" disks you need to enter some configuration commands in HPUX during the replacment process, but it can defenitely be done online(if the system is properly mirrored).

Some links with procedures are:

http://h17007.www1.hpe.com/us/en/enterprise/reference-architecture/info-library/index.aspx#.WNJ84PmGOWw

Software Recovery Handbook LVM Chapter (You find it in the Knowledge Tree of the ITRC)

The safest way is to reduce the mirror and set it up again after that, the quickest way is to

1.) unplugg the bad disk
2.) vgchange -a y /dev/vgxx #to make sure LVM noticed that the disk is unplugged
3.) insert the new disk
4.) ioscan -f # disk must be "CLAIMED"
5.) vgcfgrestore -n vgxx /dev/rdsk/ #to recreate the LVM structure on the disk
6.) vgchange -a y /dev/vgxx # LVM will scan the disks again and notice it is back
7.) vgsync vgxx #to mirror the data

best regards

Stefan

[DCE]

I would add the following to Stefan's comment because this is root drive:

perform the appropriate makeboot commands to install the boot files.

mkboot -b /dev/dsk/cxtxdx /dev/rdsk/cytydy
mkboot -a "hpux -lq" /devrdsk/cytydy

where
cxtxdx is your working mirror disk
cytydy is the new disk


The first command copies the lif files from the working mirror

the second command sets the vg so that the system will boot with only one disk.

Dave