[dm-devel] [PATCH] ALUA support for PURE FlashArray

[Brian Bunker]

Hello all,

It has been some time since we updated our PURE FlashArray configuration. The Linux vendors that we had been seeing in the field were using very old versions of multipath-tools, so we haven’t needed to change anything for some time. With the release of RHEL8, some of our earlier values have been lost by upstream changes. 

In addition we have our Active Cluster feature which leverages ALUA since our last patch. The ALUA confguration will work for all FlashArrays with or without Active Cluster.

We are changing 3 things.

1. ALUA support
2. Fast fail timeout from the default of 5 seconds to 10 seconds (We need this for our FC NPIV port migration).
3. Maximum sector size of 4MB. Some Linux vendors don’t honor the block limits VPD page of INQUIRY).

Thanks,
Brian

diff --git a/libmultipath/hwtable.c b/libmultipath/hwtable.c
index 1d964333..37e97f60 100644
--- a/libmultipath/hwtable.c
+++ b/libmultipath/hwtable.c
@@ -1024,7 +1024,12 @@ static struct hwentry default_hw[] = {
                /* FlashArray */
                .vendor        = "PURE",
                .product       = "FlashArray",
-               .pgpolicy      = MULTIBUS,
+               .pgpolicy      = GROUP_BY_PRIO,
+               .pgfailback    = -FAILBACK_IMMEDIATE,
+               .hwhandler     = "1 alua",
+               .prio_name     = PRIO_ALUA,
+               .fast_io_fail  = 10,
+               .max_sectors_kb = 4096,
        },
        /*
         * Huawei



Brian Bunker
SW Eng
brian at purestorage.com