[ovirt-users] iSCSI and multipath

[John Taylor]

On Mon, Jun 9, 2014 at 9:23 AM, Nicolas Ecarnot <nicolas at ecarnot.net> wrote:
> Le 09-06-2014 14:44, Maor Lipchuk a écrit :
>
>> basically, you should upgrade your DC to 3.4, and then upgrade the
>> clusters you desire also to 3.4.
>
>
> Well, that seems to have worked, except I had to raise the cluster level
> first, then the DC level.
>
> Now, I can see the iSCSI multipath tab has appeared.
> But I confirm what I wrote below :
>
>>>>> I saw that multipathing is talked here :
>>>>> http://www.ovirt.org/Feature/iSCSI-Multipath
>>>>>
>>>>>>     Add an iSCSI Storage to the Data Center
>>>>>>     Make sure the Data Center contains networks.
>>>>>>     Go to the Data Center main tab and choose the specific Data Center
>>>>>>     At the sub tab choose "iSCSI Bond"
>>>>>>     Press the "new" button to add a new iSCSI Bond
>>>>>>     Configure the networks you want to add to the new iSCSI Bond.
>>>>>
>>>>>
>>>>> Anyway, I'm not sure to understand the point of this wiki page and this
>>>>> implementation : it looks like a much higher level of multipathing over
>>>>> virtual networks, and not at all what I'm talking about above...?
>
>
> I am actually trying to know whether bonding interfaces (at low level) for
> the iSCSI network is a bad thing, as was told by my storage provider?
>
> --
> Nicolas Ecarnot


Hi Nicolas,
I think the naming of the managed iscsi multipathing feature a "bond"
might be a bit confusing. It's not an ethernet/nic bond, but a way to
group networks and targets together, so it's not "bonding interfaces"
Behind the scenes what it does is creates iscsi
ifaces(/var/lib/iscsi/ifaces) and changes the way the iscsiadm calls
are constructed to use those ifaces (instead of the default) to
connect and login to the targets
Hope that helps.

-John