[dm-devel] NetAPP AFF A220 - Debian - multipathing setup

[dm-devel] NetAPP AFF A220 - Debian - multipathing setup

[Thomas Glanzmann]

Hello,
I have Debian bullseye connected to an AFF A220 NetApp iSCSI target with
ALUA enabled. I see two paths, however multipathd doesn't seem to
configure a multipath device for the two paths. Find the output of the
following commands here:

dpkg -l
lsblk
sg_rtpg -vvd /dev/sde
/lib/udev/scsi_id -gud /dev/sde
sg_inq -vv -p 0x83 /dev/sdd
sg_inq -vv -p 0x83 /dev/sde
multipath -T
multipath -l

https://tg.st/u/887806617717393a1e772ca0381465f4ed8311defafeaaa26433d0a7fadf5797.txt

Cheers,
        Thomas

--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel

Re: [dm-devel] NetAPP AFF A220 - Debian - multipathing setup

[Chris Hofstaedtler]

* Thomas Glanzmann <thomas@glanzmann.de> [230222 14:15]:
> Hello,
> I have Debian bullseye connected to an AFF A220 NetApp iSCSI target with
> ALUA enabled. I see two paths, however multipathd doesn't seem to
> configure a multipath device for the two paths. Find the output of the
> following commands here:

> multipath -T

>   find_multipaths "strict"

Per multipath.conf(5):

| strict    Both multipath and multipathd treat only such devices as multipath devices which have been
|           part of a multipath map previously, and which are  therefore  listed  in  the  wwids_file.
|           Users can manually set up multipath maps using the multipathd add map command. Once set up
|           manually, the map is remembered in the wwids file and will be set up automatically in  the
|           future.

I would guess your wwids/bindings files are empty, and thus you need to
follow the advice in the manpage: use multipathd add map, or maybe
multipath -a.

If you decide to change find_multipaths, I would suggest verifying
that your resulting setup works across reboots, etc.

By the way, I think the current recommendation for modern NetApp
platforms is `prio "alua"`, not `ontap`. Would be good if NetApp
would confirm this somehow/somewhere.

Best,
Chris

--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel

Re: [dm-devel] NetAPP AFF A220 - Debian - multipathing setup

[Thomas Glanzmann]

Hello Chris,

> Per multipath.conf(5):

> | strict    Both multipath and multipathd treat only such devices as multipath devices which have been
> |           part of a multipath map previously, and which are  therefore  listed  in  the  wwids_file.
> |           Users can manually set up multipath maps using the multipathd add map command. Once set up
> |           manually, the map is remembered in the wwids file and will be set up automatically in  the
> |           future.

I wasn't aware of that. Thank you for pointing it out and resolving our issue.

> I would guess your wwids/bindings files are empty, and thus you need to
> follow the advice in the manpage: use multipathd add map, or maybe
> multipath -a.

Yes, that helped, once I executed the following commands, it works:

(live) [/etc/multipath] lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 238.5G  0 disk
sdb      8:16   1  58.9G  0 disk
├─sdb1   8:17   1   855M  0 part
└─sdb2   8:18   1     4M  0 part
sdc      8:32   0   750G  0 disk
sdd      8:48   0   750G  0 disk
sr0     11:0    1  1024M  0 rom
(live) [/etc/multipath] multipath -a /dev/sdc
wwid '3600a0980383143687224554b5472596b' added
(live) [/etc/multipath] multipath -l
(live) [/etc/multipath] cat wwids
# Multipath wwids, Version : 1.0
# NOTE: This file is automatically maintained by multipath and multipathd.
# You should not need to edit this file in normal circumstances.
#
# Valid WWIDs:
/3600a0980383143687224554b5472596b/
(live) [/etc/multipath] /etc/init.d/multipath-tools restart
Restarting multipath-tools (via systemctl): multipath-tools.service.
(live) [/etc/multipath] multipath -l
3600a0980383143687224554b5472596b dm-0 NETAPP,LUN C-Mode
size=750G features='3 queue_if_no_path pg_init_retries 50' hwhandler='1 alua' wp=rw
|-+- policy='service-time 0' prio=0 status=active
| `- 7:0:0:0 sdc 8:32 active undef running
`-+- policy='service-time 0' prio=0 status=enabled
  `- 8:0:0:0 sdd 8:48 active undef running

Cheers,
	Thomas

--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel