iSCSI Multipath and XenServer

[Manxmann]

Hey Folks,

Sorry realise this is a Xen thing but thought I'd ask the question.

I've setup a home XenServer 6.5 lab, the Xen box has 4 nics (1xMgmt, 1xVM, 2xStorage).

Mgmt Nic - 172.16.10.5/24
VM - unassigned
Storage Nic 1 - 192.168.110.50/24
Storage Nic 2 - 192.168.120.50/24

My N4F boxes has two nics:
Nic 1 - 192.168.110.150/24
Nic 2 - 192.168.120.150/24

I've enabled multi-path on XenServer then added my N4F's iSCSI target selecting the *.IQN and everything works (sort of).

[root@BIG-XEN ~]# netstat -an | grep 150
tcp 0 0 192.168.120.50:45355 192.168.120.150:3260 ESTABLISHED
tcp 0 0 192.168.110.50:54988 192.168.110.150:3260 ESTABLISHED

[root@BIG-XEN ~]# multipath -ll
330000000eeafaaf9 dm-3 FreeBSD,iSCSI DISK
size=2.0T features='0' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=1 status=active
| `- 32:0:0:0 sdf 8:80 active ready running
`-+- policy='round-robin 0' prio=1 status=enabled
`- 33:0:0:0 sdg 8:96 active ready running

However when I look at my network graphs in N4F only one nic is being used?

If I pull the 'active' nic from the back of the NAS my link fails over and I see traffic start on the second nic so based on everything I can see multipath is up and running but in what appears to be Active/Passive mode which is odd as Xen is supposedly set to default to Active/Active via Round robin, see above config.

I've now drawn a blank does anyone have any pointers?

Cheers

[Manxmann]

Solved

Remove all iSCSI config from the XenServer

Modify the /etc/multipath.conf file adding FreeBSD entry as follows:

device {
vendor "FreeBSD"
product "iSCSI Disk"
path_grouping_policy multibus
path_selector "round-robin 0"
rr_min_io 100
}

And low and behold !!

330000000eeafaaf9 dm-0 FreeBSD,iSCSI DISK
size=2.0T features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
|- 43:0:0:0 sdb 8:16 active ready running
`- 44:0:0:0 sdc 8:32 active ready running