Hi,

1)  The storage device has 2 controllers.   Each controller has 4 nics.   All 8 nics are connected to a level 2 switch that has ethernet connections to the hosts.   The storage device nics enumerated are 0, 1, 2, 3.    Controller 0, nic 0 are the primary target for a group which includes controller 1,  nic 0.   In /var/lib/iscsi/nodes/{IQN}/{nic}/default, the difference between c0n0 and c1n0 is :
# diff 10.251.6.10?,3260,?/default 
3c3
< node.tpgt = 1
---
> node.tpgt = 2
47c47
< node.conn[0].address = 10.251.6.101
---
> node.conn[0].address = 10.251.6.102

The 4 groups of nics have different subnets.  Dell docs recommend this, and the storage devices keeps packets separated by these subnets.   For my setup, I have this config:
             controller 0         controller 1        host-1                host-2
nic0   10.251.6.101      10.251.6.102     10.251.6.135      10.251.6.136
nic1   10.251.7.101      10.251.7.102     10.251.7.135      10.251.7.136
nic2   10.251.8.101      10.251.8.102     10.251.8.135      10.251.8.136
nic3   10.251.9.101      10.251.9.102     10.251.9.135      10.251.9.136

On each virtualization host, I have 1 nics configured on each of the 4 subnets.

2) We are using rhev 3.5.  I have deployed this as round-robin, not bond.   According to Dell support, iscsi works best with round-robin, whereas FC NAS works best with bond.   I follow their recommendations.   The rdac driver is setup for this, and the prio= below separates the 8 nic paths into 2 groups.

# multipath -ll
36f01faf000d7ddeb000002085258bce5 dm-1 DELL,MD32xxi
size=756G features='3 queue_if_no_path pg_init_retries 50' hwhandler='1 rdac' wp=rw
|-+- policy='round-robin 0' prio=14 status=active
| |- 7:0:0:1  sdc 8:32   active ready running
| |- 8:0:0:1  sdj 8:144  active ready running
| |- 11:0:0:1 sdu 65:64  active ready running
| `- 12:0:0:1 sdv 65:80  active ready running
`-+- policy='round-robin 0' prio=9 status=enabled
  |- 6:0:0:1  sdf 8:80   active ready running
  |- 10:0:0:1 sdk 8:160  active ready running
  |- 5:0:0:1  sdo 8:224  active ready running
  `- 9:0:0:1  sdt 65:48  active ready running

Hope this helps explain my setup.   I am not sure how to file a bug.   Is this done on bugzilla or somewhere else?

Paul


On Sun, Mar 15, 2015 at 7:44 AM, Elad Ben Aharon <ebenahar@redhat.com> wrote:
Hi Paul,

I would like to know the following details:
1) Are the hosts's NICs connected to the storage server located in the same network subnet as the storage server itself?
2) Have you tried to deploy the connection to the storage server using the 'iSCSI multipath' bond that available in RHEV-3.4?


From: "Nir Soffer" <nsoffer@redhat.com>
To: "Paul Dyer" <pmdyermms@gmail.com>
Cc: devel@ovirt.org, "Elad Ben Aharon" <ebenahar@redhat.com>
Sent: Sunday, 15 March, 2015 12:54:44 PM

Subject: Re: [ovirt-devel] adding new paths to iscsi data storage domains

Adding Elad who tested this feature lately to add more info.

----- Original Message -----
> From: "Paul Dyer" <pmdyermms@gmail.com>
> To: "Nir Soffer" <nsoffer@redhat.com>
> Cc: devel@ovirt.org
> Sent: Friday, March 13, 2015 6:25:05 PM
> Subject: Re: [ovirt-devel] adding new paths to iscsi data storage domains
>
> Nir,
>
> we have added 2 more nics to each virtualization host.    In order to get
> this working, I had to add an after_network_setup hook.   The shell script
> simply does "/sbin/iscsiadm  -m node -L all", to get the extra targets
> login after reboot.
>
> I looked in the engine table storage_server_connections and found that only
> the iscsi targets selected during the original storage domain create were
> present.   If ovirt-engine added rows here, then most of the work would
> have been done.
>
> I say mostly, because the Dell MD3200i did not return exactly the correct
> portal target values.   The device has 2 controllers, with 4 nics each.
> Controller 0, ports 0,1,2,3 uses portal target 1.    Controller 1, the
> ports uses portal target 2.   After iscsiadm discovery, the portal targets
> for ports 1,2,3 were all 1.    Ports 0 had targets 1 and 2, correctly.    I
> adjusted the values saved on the filesystem, and login/logoff works fine.
>
> Paul
>
>
>
> On Fri, Feb 6, 2015 at 11:57 AM, Paul Dyer <pmdyermms@gmail.com> wrote:
>
> > First of all, thank you for your time.   I must apologize that in this
> > install, I am using RHEV 3.4.5.    I will try to reproduce this on an ovirt
> > install.   I just need to create some paths to iscsi targets.
> >
> > 1.   This configuration has 2 physical hosts, Dell PE-R715 servers, with a
> > Dell PowerVault MD3200i iSCSI data storage domain.   The EM3 nic was the
> > original link.   EM4 was the new connection to storage.
> >
> > 2.   From the manager interface, I selected Storage tab, then the
> > kvm5DataDomain, then edit.   From the popup, I added the IP address under
> > Discovery Targets, then clicked the Discover button.    Then, clicked the
> > login arrow on the new targets discovered.
> >
> > I have attached the engine and vdsm logs.   I was working on this at about
> > 11:40am Feb 4th.
> >
> > When setting the host in maintenance mode, then reboot, and Activate, the
> > new paths do not get a login.
> >
> > Thanks,
> > Paul
> >
> >
> >
> > On Fri, Feb 6, 2015 at 5:38 AM, Nir Soffer <nsoffer@redhat.com> wrote:
> >
> >> ----- Original Message -----
> >> > From: "Paul Dyer" <pmdyermms@gmail.com>
> >> > To: devel@ovirt.org
> >> > Sent: Friday, February 6, 2015 12:20:23 AM
> >> > Subject: [ovirt-devel] adding new paths to iscsi data storage domains
> >> >
> >> > Hi,
> >> >
> >> > I have been reading the devel list for months now, and would like to
> >> ask a
> >> > question.
> >> >
> >> > In version 3.4.5, adding new paths to an existing iSCSI data storage
> >> domain
> >> > does not work from the manager.
> >>
> >> It works on ovirt 3.5 and master and it should work also in all previous
> >> versions.
> >>
> >> Please open a bug for this:
> >> 1. Describe the configuration you are modifying
> >> 2. Describe the steps you take
> >> 3. Include engine log
> >> 4. Include vdsm log from the host trying to add new devices
> >>
> >> > I have been able to add the paths with
> >> > command line "iscsiadm -m discovery -t st" and "iscsiadm -m node -L
> >> all".
> >> >
> >> > Is there any plan to allow for adding new storage paths after the data
> >> domain
> >> > has been created?
> >> >
> >> > Thanks,
> >> > Paul
> >> >
> >> >
> >> > --
> >> > Paul Dyer,
> >> > Mercury Consulting Group, RHCE
> >> > 504-302-8750
> >> >
> >> > _______________________________________________
> >> > Devel mailing list
> >> > Devel@ovirt.org
> >> > http://lists.ovirt.org/mailman/listinfo/devel
> >>
> >
> >
> >
> > --
> > Paul Dyer,
> > Mercury Consulting Group, RHCE
> > 504-302-8750
> >
>
>
>
> --
> Paul Dyer,
> Mercury Consulting Group, RHCE
> 504-302-8750
>




--
Paul Dyer,
Mercury Consulting Group, RHCE
504-302-8750