XENSERVER 6 Multipathing only one path

[MarcMoennikes]

Hello,

i am trying to use multipathing with starwind 5.8 and xenserver 6.0.2.
My xenserver has 2 nics configured with seperate ip subnets and the starwind server has also 2 nics.
I have created a device and a target for the xenserver.
I have enabled multipathing in the properties of the xenserver. When i add the iSCSI storage i am entering both starwind ips for the target host with ,:
172.31.248.1,172.31.249
When i Discover IQNs i can select *(172.31.248.1,172.31.249.1:3260) and also discover LUNs.
After adding the LUN the xencenter is showing only one path and this path as active.
When i look at the starwind console i can only see one iscsi session....

I have created 2 additional image file devices. And created 2 additional targets.
I have created 2 rules for the access rights. For every iscsi ip subnet a specific target.
I can connect from the xenserver both targets. So the physical iscsi connection and ip configuration seems to be ok.

Is there anything else i need to configure for xenserver and starwind?

Regards

[Anatoly (staff)]

Dear MarcMoennikes,

Would you kindly doublecheck if you have configured everything according to our manual that you can download below?
http://www.starwindsoftware.com/providi ... -xenserver

[MarcMoennikes]

Hello,

i have read the manual. There are 2 differences between the scenario in the whitepaper an my.
First, i have no HA environmant.
Second: My starwind server has 3 nics. one nic for management, 2nd and 3rd nic for iscsi traffic with different subnets on seperate switches.
one nic has ip 172.31.248.1/24, second 172.31.249.1
my xenserver has 2 nics for iscsi, ip 172.31.248.2 and 172.31.249.2.
I have created a device and the a target. i have added a rule that allows 172.31.248.2 and 172.31.249.2 to connect to the target.

I have also tried to execute iscsiadm -m discovery -t st -p 172.31.248.1:3260
and iscsiadm -m discovery -t st -p 172.31.249.1:3260
and also used iscsiadm -m node -T iqn.2008-08.com.starwindsoftware:192.168.1.225-xenserverstorage -p 192.168.1.225:3260 -l with my iqn's.

After that on the xenserver i have seen 2 paths to the starwindserver, but after a reboot only one path was available and active.

Regards

[MarcMoennikes]

Hello,

i have made 2 additional changes:
i have edited the starwind.cfg and there uncommented the <iscsidiscoverylistInterfaces value="1" />

also i have changed in the starwind console the following parameter in the advanced section:
Max Receive Data Segmnent Length to the same which is in the pdf.
I have made the registry changes in the pdf also, but the value in the console was 6556 or so.

After that i can add the iscsi target, 2 paths from 2 are active and also after a reboot.

I am not sure, which change has helped.
I have also found a word document "HA XEN Guide.docx". This settings i have made on one xenserver. Other xenserver is default configured. Both xenserver can not connect with both path to the target. So the settings made in the document seems not to be relevant.

Maybe somebody from starwind can reply:
a) is iscsidiscoverylistInterfaces change needed?
b) is the registry value in the pdf and the value in the advanced settings the same?
c) is the docx file relevant?

Thank you

Regards

[Anatoly (staff)]

Dear Marc,

a) is iscsidiscoverylistInterfaces change needed?

It is needed when using HA

b) is the registry value in the pdf and the value in the advanced settings the same?

No. I mean if you changing one, another one will not change.

c) is the docx file relevant?

I`m actually not pretty sure what document are you talking about. Would you please provide us with it and tell where have you found it?

the value in the console was 6556 or so.

Are you sure that you haven`t missed one number in this value?

And I`m sorry, but I am a little bit confud=sed now - is second path is establishing after server was rebooted?

[MarcMoennikes]

Hello,
i have attached the docx.
The value was 65536 (defualt), now i have 262144 for Max Receive Data Segment Length.
Change was made in the starwind console.
And i have changed the entry in the cfg file.

Before i changed this settings, the xenserver was finding only one path.
I have tried it 8 times or so.
Only one time i have seen 2 pathes in the xenserver console, but after restarting the xenserver only one path available and active.
I have tried it with 2 xenservers no luck.

Well, now, both xenserver can see 2 pathes. Added the storage to the xenserver with the xencenter gui and everything ok.
Also loosing one path (unplugging cable) ok, after plugging in both paths active.
Restarted several times, every time 2 pathes

Regards

[Max (staff)]

Glad to hear that MPIO is functioning again!
I usually made it working by changing the multipath.conf
I added user_friendly_names no, polling_interval_10 and path_grouping_policy group_by_prio/multibus
You can also override to one path by using "failover" value for the path grouping policy parameter.