action #105449
Updated by geor about 2 years ago
### This ticket requires that poo#105440 has been completed.
## Motivation
The FCP topology on our z/VM testing infrastructure has recently been updated and the [zfcp testsuite](https://openqa.suse.de/tests/latest?distri=sle&flavor=Online&test=zfcp&version=15-SP4) needs a new test module to validate multipathing.
## Task
The idea is to check the status of the known infrastructure, and the status of multipathing on top of it.
**AC1**: Verify that there are two host bus adapters attached, and that the corresponding channels (`0.0.fa00, 0.0.fc00`) are listed
```
# ls -l /sys/class/fc_host
total 0
lrwxrwxrwx 1 root root 0 Dec 19 17:53 host0 -> ../../devices/css0/0.0.0005/0.0.fa00/host0/fc_host/host0
lrwxrwxrwx 1 root root 0 Dec 19 17:53 host1 -> ../../devices/css0/0.0.0006/0.0.fc00/host1/fc_host/host1
```
**AC2**: Based on the output of lsscsi:
```
# lsscsi -xxgst
[0:0:0:0x4001403200000000] disk fc:0x500507630703d3b30x760f00 /dev/sda /dev/sg0 214GB
[0:0:0:0x4001405000000000] disk fc:0x500507630703d3b30x760f00 /dev/sdb /dev/sg1 42.9GB
[0:0:1:0x4001403200000000] disk fc:0x500507630708d3b30x761000 /dev/sdc /dev/sg2 214GB
[0:0:1:0x4001405000000000] disk fc:0x500507630708d3b30x761000 /dev/sdd /dev/sg3 42.9GB
[1:0:0:0x4001403200000000] disk fc:0x500507630718d3b30x771000 /dev/sde /dev/sg4 214GB
[1:0:0:0x4001405000000000] disk fc:0x500507630718d3b30x771000 /dev/sdf /dev/sg5 42.9GB
[1:0:1:0x4001403200000000] disk fc:0x500507630713d3b30x770f00 /dev/sdg /dev/sg6 214GB
[1:0:1:0x4001405000000000] disk fc:0x500507630713d3b30x770f00 /dev/sdh /dev/sg7 42.9GB
```
* verify that there are 8 SCSI block devices listed (as a result of having two adapters, two hard disks and two paths to each disk, 2^3 = 8)
* verify that LUN `0x4001403200000000` corresponds to the 214GB disk, and LUN `0x4001405000000000` to the 42.9GB disk
**AC3**: Based on the output of multipath -l:
```
# multipath -l
36005076307ffd3b30000000000000132 dm-0 IBM,2107900
size=200G features='1 queue_if_no_path' hwhandler='1 alua' wp=rw
`-+- policy='service-time 0' prio=0 status=enabled
|- 0:0:0:1077035009 sda 8:0 active undef running
|- 0:0:1:1077035009 sdc 8:32 active undef running
|- 1:0:0:1077035009 sde 8:64 active undef running
`- 1:0:1:1077035009 sdg 8:96 active undef running
36005076307ffd3b30000000000000150 dm-41 IBM,2107900
size=40G features='1 queue_if_no_path' hwhandler='1 alua' wp=rw
`-+- policy='service-time 0' prio=0 status=enabled
|- 0:0:0:1079001089 sdb 8:16 active undef running
|- 0:0:1:1079001089 sdd 8:48 active undef running
|- 1:0:1:1079001089 sdh 8:112 active undef running
`- 1:0:0:1079001089 sdf 8:80 active undef running
```
* verify that the multipath device with WWID `36005076307ffd3b30000000000000132` corresponds to the 200G disk and the multipath device with WWID `36005076307ffd3b30000000000000150` to the 40G disk
* verify that there are 4 block devices listed for each virtual multipath device
## Suggestion
It might help to check [this confluence article](https://confluence.suse.com/display/QYT/Mainframe+Musings%3A+Playing+around+with+FCP+and+multipath#MainframeMusings:PlayingaroundwithFCPandmultipath-Faulttoleranceinaction) for some more insight on the output of the above commands.