[dm-devel] [PATCH] multipath-tools: make IBM/2107900 (DS8000) config work with alua and multibus

[Martin Wilck]

On Tue, 2021-09-28 at 18:52 +0200, Xose Vazquez Perez wrote:
> ALUA is supported since the beginning:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/scsi/device_handler/scsi_dh_alua.c?id=057ea7c9683c3d684128cced796f03c179ecf1c2#n683
> 
> ... the DS8000 is an Asymmetric Logical Unit Access (ALUA) capable
> storage array,
> pag#160(144): https://www.redbooks.ibm.com/redbooks/pdfs/sg248887.pdf
> 
> kernel log:
> https://marc.info/?l=linux-scsi&m=156407413807511&q=mbox
> 
> Cc: Martin Wilck <mwilck at suse.com>
> Cc: Benjamin Marzinski <bmarzins at redhat.com>
> Cc: Christophe Varoqui <christophe.varoqui at opensvc.com>
> Cc: DM-DEVEL ML <dm-devel at redhat.com>
> Signed-off-by: Xose Vazquez Perez <xose.vazquez at gmail.com>

Thanks for the careful investigation!

Reviewed-by: Martin Wilck <mwilck at suse.com>

> ---
>  libmultipath/hwtable.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/libmultipath/hwtable.c b/libmultipath/hwtable.c
> index 72f81c60..f115c4f9 100644
> --- a/libmultipath/hwtable.c
> +++ b/libmultipath/hwtable.c
> @@ -656,7 +656,8 @@ static struct hwentry default_hw[] = {
>                 .vendor        = "IBM",
>                 .product       = "^2107900",
>                 .no_path_retry = NO_PATH_RETRY_QUEUE,
> -               .pgpolicy      = MULTIBUS,
> +               .pgpolicy      = GROUP_BY_PRIO,
> +               .pgfailback    = -FAILBACK_IMMEDIATE,
>         },
>         {
>                 // Storwize V5000 and V7000 lines / SAN Volume
> Controller (SVC) / Flex System V7000 /