Difference between revisions of "SAN relocation task"
| Line 1: | Line 1: | ||
= Introduction = | = Introduction = | ||
| − | During Dec 2017 and Jan 2018, Ally Kirk rang up to say IT Services were doing some | + | During Dec 2017 and Jan 2018, Ally Kirk rang up to say IT Services were doing some relocation on their SAN which is where marvin's STORAGE volume is located. The whole process is transparent, but it would be useful to have been supervise thigns operationally, just in case anything went wrong. |
= Tasks = | = Tasks = | ||
| − | Pretty similar to any changes that may occur on this volume: scan SCSI | + | Pretty similar to any changes that may occur on this volume: |
| + | * scan SCSI | ||
| + | * use multipath -ll to see what need device some up. | ||
| − | = Read-outs = | + | = Read-outs prior to change-over = |
root@marvin:/storage/home/users/ramon > multipath -ll | root@marvin:/storage/home/users/ramon > multipath -ll | ||
| Line 34: | Line 36: | ||
`- 7:0:0:1 sdj 8:144 active undef unknown | `- 7:0:0:1 sdj 8:144 active undef unknown | ||
| − | = Things to check = | + | == Things to check == |
How are the devices looking? Go to | How are the devices looking? Go to | ||
| Line 42: | Line 44: | ||
However, this exercise didn't really reveal anything | However, this exercise didn't really reveal anything | ||
| − | = After the | + | = After the change-over = |
mpathd (36000d3100051f800000000000000016e) dm-6 COMPELNT,Compellent Vol | mpathd (36000d3100051f800000000000000016e) dm-6 COMPELNT,Compellent Vol | ||
| Line 63: | Line 65: | ||
"SCSI id numbers coincide with previous scan output, new device names. Though a bit clueless about the process, it looks to me as though both sets of paths (4 devices each) were working simultaneously, and what happened was, in the changeover, the first set was pulled and we're seeing the second set stand on its own two feet (so to speak)." | "SCSI id numbers coincide with previous scan output, new device names. Though a bit clueless about the process, it looks to me as though both sets of paths (4 devices each) were working simultaneously, and what happened was, in the changeover, the first set was pulled and we're seeing the second set stand on its own two feet (so to speak)." | ||
| + | |||
| + | He verified this, so that "failed faulty running" is entirely expected, as the old SAN multipaths are withdrawn. | ||
Latest revision as of 15:44, 25 January 2018
Contents
Introduction
During Dec 2017 and Jan 2018, Ally Kirk rang up to say IT Services were doing some relocation on their SAN which is where marvin's STORAGE volume is located. The whole process is transparent, but it would be useful to have been supervise thigns operationally, just in case anything went wrong.
Tasks
Pretty similar to any changes that may occur on this volume:
- scan SCSI
- use multipath -ll to see what need device some up.
Read-outs prior to change-over
root@marvin:/storage/home/users/ramon > multipath -ll mpathd (36000d3100051f800000000000000016e) dm-6 COMPELNT,Compellent Vol size=62T features='1 queue_if_no_path' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=active |- 6:0:0:1 sdd 8:48 active ready running |- 7:0:6:1 sdf 8:80 active ready running |- 6:0:1:1 sde 8:64 active ready running |- 7:0:7:1 sdg 8:96 active ready running |- 6:0:4:1 sdh 8:112 active ready running |- 7:0:1:1 sdk 8:160 active ready running |- 6:0:5:1 sdi 8:128 active ready running `- 7:0:0:1 sdj 8:144 active ready running root@marvin:/storage/home/users/ramon > multipath -l mpathd (36000d3100051f800000000000000016e) dm-6 COMPELNT,Compellent Vol size=62T features='1 queue_if_no_path' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=0 status=active |- 6:0:0:1 sdd 8:48 active undef unknown |- 7:0:6:1 sdf 8:80 active undef unknown |- 6:0:1:1 sde 8:64 active undef unknown |- 7:0:7:1 sdg 8:96 active undef unknown |- 6:0:4:1 sdh 8:112 active undef unknown |- 7:0:1:1 sdk 8:160 active undef unknown |- 6:0:5:1 sdi 8:128 active undef unknown `- 7:0:0:1 sdj 8:144 active undef unknown
Things to check
How are the devices looking? Go to
/sys/block/sdg/device
for sdg (similarly for sdd, sde, sdf)
However, this exercise didn't really reveal anything
After the change-over
mpathd (36000d3100051f800000000000000016e) dm-6 COMPELNT,Compellent Vol size=62T features='1 queue_if_no_path' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=active |- 6:0:0:1 sdd 8:48 failed faulty running |- 7:0:6:1 sdf 8:80 failed faulty running |- 6:0:1:1 sde 8:64 failed faulty running |- 7:0:7:1 sdg 8:96 failed faulty running |- 6:0:4:1 sdh 8:112 active ready running |- 7:0:1:1 sdk 8:160 active ready running |- 6:0:5:1 sdi 8:128 active ready running `- 7:0:0:1 sdj 8:144 active ready running
Because all eight of these devices were
active ready running
previously, I wrote to Ally with my understanding of the process:
"SCSI id numbers coincide with previous scan output, new device names. Though a bit clueless about the process, it looks to me as though both sets of paths (4 devices each) were working simultaneously, and what happened was, in the changeover, the first set was pulled and we're seeing the second set stand on its own two feet (so to speak)."
He verified this, so that "failed faulty running" is entirely expected, as the old SAN multipaths are withdrawn.
