Hot swap N4000 system disk?

[Joe Profaizer]

Is this possible or does it require downtime since the disk is enclosed in the back chassis of the system?

Thanks.

[Pete Randall · Accepted solution]

No downtime, Joe, it is indeed hot swappable, despite it's location. I've done so myself.


Pete

[Torsten.]

It is hot-pluggable, but be careful and don't pull both drives ;-)

[Joe Profaizer]

Since this disk was the primary, and we mirrored the logical volumes are there any prerequisite steps and/or post installation steps that are recommended? Currently the device shows a NO_HW status (0/0/2/0.6.0).

Thanks so much.

[TwoProc]

It's hot-swappable, just be slow and deliberate in your moves when you move the chassis, being careful not to stretch, disconnect, or tear wiring still attached to the back of the system or adjacent systems. Then carefully proceed to make your way to the drive, carefully avoiding disturbing all other components, and you'll be fine. Don't forget to wear your anti-static discharge grounding strap!

[Pete Randall]

Here is an excellent guide to replacing disks:

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad.pdf


Pete

[Josiah Henline]

The drive can be hot-swapped if it shows as unavailable in a vgdisplay.

vgdisplay -v /dev/vg01|more
--- Volume groups ---
VG Name /dev/vg01
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 2 <- the drive must show to not be available. In this case it must be a 1 and not a 2.
Max PE per PV 4341
VGDA 4
PE Size (Mbytes) 4
Total PE 8680
Alloc PE 8680
Free PE 0
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

--- Logical volumes ---
LV Name /dev/vg01/lvol1
LV Status available/syncd
LV Size (Mbytes) 34720
Current LE 8680
Allocated PE 8680
Used PV 2


--- Physical volumes ---
PV Name /dev/dsk/c0t9d0
PV Status available
Total PE 4340
Free PE 0
Autoswitch On

PV Name /dev/dsk/c0t10d0
PV Status available <- the drive must show to not be available.
Total PE 4340
Free PE 0
Autoswitch On


Also, if your system is 11.0, it is a good idea to reboot the system off of the mirrored/good root drive before replacing it. From experience, 11.0 at some LVM patching levels can cause inode corruption if the primary root disk is hot-swapped.

[TwoProc]

An interesting thread:
http://forums1.itrc.hp.com/service/forums/questionanswer.d
o?threadId=140137

And also this interesting thread:

https://forums1.itrc.hp.com/service/forums/questionanswer
.do?threadId=1033211

[Denver Osborn]

if the PV is unattached from the VG (showing NO_HW in ioscan), then I see no prob w/ a hot swap.

I'm sure one of the links to docs already posted will show the steps for replacing an unattached mirrored boot disk... pretty much replace it, vgcfgrestore, vgchange, mkboot then lifcp online diags stuff... lvlnboot -R

-denver

[rick jones]

Be very careful with terminology. IIRC:

*) "hot-swap" means one can just walk-up, pull the drive, put-in a new one, and all the right things happen automagically - like when does that with an external disc array

*) "hot-plub" means simply that one will not fry the electronics if you pull the drive. it does _not_ mean that all the other right things will happen automagically. It may be the case that one has to execute certain commands before pulling the drive and after inserting the new one.

IIRC the disc bays in the N4000 are _hot-plug_ not _hot-swap_