From: Mike Christie <mchristi@redhat.com>
Date: Thu, 18 Feb 2010 23:38:31 -0500
Subject: [scsi] device_handler: add netapp to alua dev list
Message-id: <1266536311-2806-1-git-send-email-mchristi@redhat.com>
Patchwork-id: 23358
O-Subject: [PATCH 1/1] RHEL 5.5: Add netapp to scsi dh alua dev list
Bugzilla: 562080
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

From: Mike Christie <mchristi@redhat.com>

Netapp is now supporting ALUA, and is hitting a bug
where they get:

kernel: sd 7:0:0:1: Device not ready: <6>: Current: sense key: Not Ready
kernel:     Add. Sense: Logical unit not accessible, asymmetric access
state transition

and the IO is failed.

This is a retryable error, and the scsi_dh_alua is already set up
to detect and retry it. Netapp devices are not yet in the alua
list though, so this patch adds their boxes to it.

I have just sent the patch to the linux-scsi list.
http://marc.info/?l=linux-scsi&m=126653579625086&w=2

Patch was made and tested by Netapp. I do not have any netpapp boxes
that support this feature and the netapp sim does not either,
so I just ran with the patch to check that it fails correctly
on older boxes that do not support alua.


diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 1c16a40..0315aa1 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -700,6 +700,7 @@ const struct scsi_dh_devlist alua_dev_list[] = {
 	{"DGC", "RAID"},
 	{"DGC", "DISK"},
 	{"DGC", "VRAID"},
+	{"NETAPP", "LUN"},
 	{NULL, NULL}
 };