iSCSI multi-path issues in v5?

[Titans99]

Hi, I'm having a terrible time configuring iSCSI hba's for multi-pathing in ESXi 5.  It is working fine on ESXi 4, so I am trying to duplicate that same config on two new v5 hosts (DL385 G7).

Each of the VMkernel ports are configured to use a single vmnic (one active, one unused)

Each vmhba has two paths to the storage (vmhba34 and vmhba36 in this case).  Where vmhba34 has static discovery IP's to the storage at 10.1.10.12 and 10.1.10.13.  vmhba36 has static discovery IP's to the storage at 10.1.20.12 and 10.1.20.13. (the SAN unit is a p2000 G3 with 4 nics)

After I initially add the static discovery, then rescan all, I see all FOUR paths show up to each LUN - two for each hba. As soon as I reboot the server, only two paths are available which are through vmhba34.  vmhba36 shows ZERO paths or LUN's even if I rescan.

If I remove the static discovery IP's and add them back, I can see all FOUR paths again until I reboot.  NOTE:  If I create a separate vSwitch for each VMkernel port, then all works well even after reboot. 

Is this a known issue in ESXi 5?  Are there any drawbacks to using separate vSwitches for each VMkernel port?  Any help is appreciated as I'm losing my hair!

[krowczynski]

HI,

had the same issue until I read the documents on vmware page.

We also have two differents Networks for ISCSI, so I had configured it the same way it was in vSPhere 4.1, but after reboot I did not see any Datastore on my hosts.

So I configured seperate vswitches for each iscsi connection and no it works fine.

[Titans99]

Glad I'm not losing my mind then.  I could not find any docs relating to this issue - did you say you found one?

[scottyyyc]

Hmmm, this might be a stretch, but I remember having a somewhat similar issue when setting up 4.1, where no matter what I tried, I just couldn't get all the paths working at the same time. I spent the better part of an afternoon with a Dell EqualLogic tech trying to figure it out, when I ran across some Dell documentation that noted that by default, ESXi will only use one vmk port at any given time for iSCSI connections, multipathing aside.

So there's a command you have to run on the ESXi box to allow iSCSI to use multiple vmk ports simultaneously. Give this document (http://www.vmware.com/pdf/vsphere4/r40/vsp_40_iscsi_san_cfg.pdf) a look over around page 37. I can't find the original Dell document, but this is the same thing.

I had to do this on 4.1, but didn't have to do in on 5.0 - mind you I upgraded, so this probably carried over.

From the document:

Example: Connecting Software iSCSI Initiator to Two VMkernel Ports

This example shows how to connect the software iSCSI initiator vmhba33 to VMkernel ports vmk1 and vmk2.

1 Connect vmhba33 to vmk1:

esxcli swiscsi nic add -n vmk1 -d vmhba33

2 Connect vmhba33 to vmk2:

esxcli swiscsi nic add -n vmk2 -d vmhba33

3 Verify vmhba33 configuration:

esxcli swiscsi nic list -d vmhba33

Both vmk1 and vmk2 should be listed.

In this example, if you use the vSphere client