[dm-devel] multipath failover with 2x Emulex LP9802, setup, WWIDs

[Lars Marowsky-Bree]

On 2004-11-25T08:55:09, Andreas Huck <dm-devel at huck.it> wrote:

> First, how to get a WWID?  I have 4 devices with 2 paths each.
> `scsidev -s` should provide it but doesn't:
> 
> # scsidev -s
> Serial number of /dev/scsi/sgh1-1c0i0l3: "0003cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh1-0c0i0l3: "0003cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh1-1c0i0l2: "0002cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh1-0c0i0l2: "0002cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh1-1c0i0l1: "0001cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh1-0c0i0l1: "0001cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh1-1c0i0l0: "0000cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh1-0c0i0l0: "0000cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh0-0c0i0l3: "0003cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh0-0c0i0l3: "0003cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh0-0c0i0l2: "0002cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh0-0c0i0l2: "0002cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh0-0c0i0l1: "0001cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh0-0c0i0l1: "0001cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0
> Serial number of /dev/scsi/sgh0-0c0i0l0: "0000cc7420000080e512cc740000000000000000"
> Serial number of /dev/scsi/sdh0-0c0i0l0: "0000cc7420000080e512cc740000000000000000"
>  HSV OS Id: 0

There are 4 distinct WWIDs in there; I fail to see your problem?

This should work mostly out of the box.

> I tried a direct approach by dmsetup, but didn't get a device:
> 
> # echo "0 274968576 multipath 10 2 1 round-robin 1 0 \
> /dev/sdb 1 round-robin 1 0 /dev/sdf" | dmsetup create /dev/dm-0
> k_set_name: Device /dev/dm-0 not found
> Command failed

This is the wrong syntax for dmsetup; you need to give a table name.
"dmsetup create whatever" would create the appropriate table.

> # /sbin/devmap_name 8 16
> No devices found

No wonder, there's no device map for 8:16, it's a SCSI device.

> Do I overlook something important here?

Yes. Try reading the documentation again ;-)


Sincerely,
    Lars Marowsky-Brée <lmb at suse.de>

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