This question also asked at Citrix Forums http://forums.citrix.com/thread.jspa?threadID=332289 I have a MD3200i that is currently working fine with my Xen5.6 pool, but I cannot get a connection to the new 6.2 pool to work. I previously had a problem with a 6.0 upgrade (which is why the old pool is still on 5.6), but rolled back rather than fix it as it wasn't urgent at the time. This install is on new machines - I tried 6.1 first (which had the same problems) then 6.2 was released the second day after installation so I switched to that. I've not installed anything from the Dell resource DVD at this point - I can't find anything saying I should, and everything I have read suggests it shouldn't be necessary. I can ping all 8 ip addresses from both servers in the pool, iscsiadm -m discovery works fine, I can login to the nodes and iscsiadm reports the sessions active correctly. I've added the required sections to multipath.conf, but multipath -ll reports DM multipath kernel driver not loaded immediately after boot. The following is a log of a test session immediately after boot. root@xen3 ~]# iscsiadm -m node --loginall=all Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.101,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.101,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.104,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.102,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.103,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.104,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.102,3260] Logging in to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.103,3260] Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.101,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.101,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.104,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.102,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.103,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.104,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.130.102,3260]: successful Login to [iface: default, target: iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91, portal: 192.168.131.103,3260]: successful [root@xen3 ~]# iscsiadm -m session tcp: [1] 192.168.130.101:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [2] 192.168.131.101:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [3] 192.168.131.104:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [4] 192.168.131.102:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [5] 192.168.130.103:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [6] 192.168.130.104:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [7] 192.168.130.102:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [8] 192.168.131.103:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 [root@xen3 ~]# service multipathd restart ok Stopping multipathd daemon: [ OK ] Starting multipathd daemon: [ OK ] [root@xen3 ~]# multipath Jul 04 09:58:47 | DM multipath kernel driver not loaded Jul 04 09:58:47 | DM multipath kernel driver not loaded [root@xen3 ~]# multipath -ll Jul 04 09:59:03 | DM multipath kernel driver not loaded Jul 04 09:59:03 | DM multipath kernel driver not loaded [ root@xen3 ~]# modprobe dm_multipath [root@xen3 ~]# multipath Jul 04 10:19:50 | 36b8ca3a0e7024800194a0bd11891cd14: ignoring map create: 1Dell_Internal_Dual_SD_0123456789AB undef Dell,Internal Dual SD size=1.9G features='0' hwhandler='0' wp=undef `-+- policy='round-robin 0' prio=1 status=undef `- 7:0:0:0 sdb 8:16 undef ready running [root@xen3 ~]# multipath -ll 1Dell_Internal_Dual_SD_0123456789AB dm-1 Dell,Internal Dual SD size=1.9G features='0' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=enabled `- 7:0:0:0 sdb 8:16 active ready running [root@xen3 ~]# iscsiadm -m session tcp: [1] 192.168.130.101:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [2] 192.168.131.101:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [3] 192.168.131.104:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [4] 192.168.131.102:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [5] 192.168.130.103:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [6] 192.168.130.104:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [7] 192.168.130.102:3260,2 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 tcp: [8] 192.168.131.103:3260,1 iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 [root@xen3 ~]# dmesg | tail -n 50 [ 1161.881010] sd 8:0:0:0: [sdf] Unhandled error code [ 1161.881013] sd 8:0:0:0: [sdf] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1161.881017] sd 8:0:0:0: [sdf] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1161.881024] end_request: I/O error, dev sdf, sector 0 [ 1161.881031] Buffer I/O error on device sdf, logical block 0 [ 1161.881045] sd 15:0:0:0: [sdi] Unhandled error code [ 1161.881048] sd 15:0:0:0: [sdi] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1161.881052] sd 15:0:0:0: [sdi] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1161.881058] end_request: I/O error, dev sdi, sector 0 [ 1161.881065] Buffer I/O error on device sdi, logical block 0 [ 1161.881122] sd 9:0:0:0: [sdg] Unhandled error code [ 1161.881124] sd 9:0:0:0: [sdg] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1161.881126] sd 9:0:0:0: [sdg] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1161.881132] end_request: I/O error, dev sdg, sector 0 [ 1161.881140] Buffer I/O error on device sdg, logical block 0 [ 1168.220951] connection6:0: ping timeout of 15 secs expired, recv timeout 10, last rx 84060, last ping 85060, now 86560 [ 1168.220957] connection7:0: ping timeout of 15 secs expired, recv timeout 10, last rx 84060, last ping 85060, now 86560 [ 1168.220967] connection7:0: detected conn error (1011) [ 1168.220969] connection4:0: ping timeout of 15 secs expired, recv timeout 10, last rx 84060, last ping 85060, now 86560 [ 1168.220973] connection4:0: detected conn error (1011) [ 1168.220975] connection3:0: ping timeout of 15 secs expired, recv timeout 10, last rx 84060, last ping 85060, now 86560 [ 1168.220978] connection3:0: detected conn error (1011) [ 1168.220985] connection6:0: detected conn error (1011) [ 1168.480994] sd 14:0:0:0: [sde] Unhandled error code [ 1168.480998] sd 14:0:0:0: [sde] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1168.481001] sd 14:0:0:0: [sde] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1168.481009] end_request: I/O error, dev sde, sector 0 [ 1168.481015] Buffer I/O error on device sde, logical block 0 [ 1168.481076] sd 11:0:0:0: [sdc] Unhandled error code [ 1168.481078] sd 11:0:0:0: [sdc] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1168.481080] sd 11:0:0:0: [sdc] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1168.481087] end_request: I/O error, dev sdc, sector 0 [ 1168.481092] Buffer I/O error on device sdc, logical block 0 [ 1168.481144] sd 10:0:0:0: [sdd] Unhandled error code [ 1168.481147] sd 10:0:0:0: [sdd] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1168.481150] sd 10:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1168.481156] end_request: I/O error, dev sdd, sector 0 [ 1168.481163] Buffer I/O error on device sdd, logical block 0 [ 1168.481168] sd 13:0:0:0: [sdj] Unhandled error code [ 1168.481170] sd 13:0:0:0: [sdj] Result: hostbyte=DID_TRANSPORT_DISRUPTED driverbyte=DRIVER_OK [ 1168.481172] sd 13:0:0:0: [sdj] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 1168.481178] end_request: I/O error, dev sdj, sector 0 [ 1168.481184] Buffer I/O error on device sdj, logical block 0 [ 1457.105996] device-mapper: multipath round-robin: version 1.0.0 loaded [ 1457.106155] device-mapper: multipath: Cannot access device path 8:0: -16 [ 1457.106164] device-mapper: table: 252:1: multipath: error getting device [ 1457.106172] device-mapper: ioctl: error adding target to table [ 1457.171292] device-mapper: multipath: Cannot access device path 8:0: -16 [ 1457.171299] device-mapper: table: 252:1: multipath: error getting device [ 1457.171304] device-mapper: ioctl: error adding target to table [root@xen3 ~]# fdisk -l Disk /dev/sda: 299.4 GB, 299439751168 bytes 255 heads, 63 sectors/track, 36404 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sda1 1 5 40131 de Dell Utility /dev/sda2 * 6 528 4194304 83 Linux Partition 2 does not end on cylinder boundary. /dev/sda3 528 1050 4194304 83 Linux /dev/sda4 1050 36404 283986359+ 8e Linux LVM Disk /dev/sdb: 2040 MB, 2040528896 bytes 255 heads, 63 sectors/track, 248 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sdb1 1 248 1992028+ 83 Linux Disk /dev/dm-1: 2040 MB, 2040528896 bytes 255 heads, 63 sectors/track, 248 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/dm-1p1 1 248 1992028+ 83 Linux [root@xen3 ~]# xe sr-probe type=lvmoiscsi device-config:target=192.168.130.101 device-config:targetIQN=iqn.1984-05.com.dell:powervault.md3200i.6782bcb0006bd850000000004ed88b91 Error code: SR_BACKEND_FAILURE_107 Error parameters: , The SCSIid parameter is missing or incorrect, <?xml version="1.0" ?> <iscsi-target/> Note: the xml ends there correctly on the last line - it doesn't ever return a list of LUNs (and there is one in the group on the SAN for those servers.