iscsi with Etherchannel isn't working

[aolabisi]

is there any reason why a qlogic iscsi initiator can't establish an iscsi session with an IPS module via a port-channel interface? it successfully establishes a session with a single interface on the same IPS module.

dayo

[mrfrase]

Should work, would like to see Ethernet switch configuration and IPS8 config. What version firmware are you running on the Qlogic iSCSI HBA. We may need a TAC case open to dig into this and run debugs.

[tblancha]

You will need to define the port-channel groups under the ethernet interfaces and have the IP address on the port-channel logical interface as the target IP address. This will not work on the 14+2 cards. Is your initiator able to ping the target IP address? If not, then it is not an iscsi issue as a IP connectivity issue.

[aolabisi]

My scsi initiator is able to poing the IP address of the port-channel logical interace. I have an IPS-8 module on an mds9509.

if you have access to Cisco TAC cases, I opened a case - check out my "show tech" on case 600848444.

the SE assigned to the case is in Australia - we have a 24-hour turnaround time for mail exchanges... i send him a mail and expect a response the next day.

dayo

[tarun.pahuja]

Dayo,

Can you please upload relavent parts of the configuration or paste it, please.

Thanks,

Tarun

[aolabisi]

here you go:

on the MDS:

interface port-channel 1

switchport trunk mode off

ip address 172.16.1.1 255.255.255.0

interface GigabitEthernet7/1

channel-group 1 force

no shutdown

interface GigabitEthernet7/2

channel-group 1 force

no shutdown

interface GigabitEthernet7/3

ip address 172.16.1.3 255.255.255.0

no shutdown

on the Cat3750:

interface Port-channel1

switchport mode access

no ip address

interface GigabitEthernet1/0/25

switchport mode access

no ip address

speed nonegotiate

channel-group 1 mode on

interface GigabitEthernet2/0/25

switchport mode access

no ip address

speed nonegotiate

channel-group 1 mode on

interface GigabitEthernet2/0/24

description iSCSI initiator port

switchport mode access

no ip address

speed nonegotiate

I can establish an iSCSI session successfully to 172.16.1.3 (individual port), but I can't establish one to 172.16.1.1

it's the same initiator/target, so the configs are the same on the MDS. I advertise the target on int po1, g7/1, g7/2 and g7/3. all ports are in the same zone and there's no iscsi authentication and no iscsi acl.

dayo

[aolabisi]

turns out to be a bug in San-OS. Other iscsi initiators are more forgiving - but the Qlogic HBAs I have are not as forgiving... see comments from SE working on the case I opened below:

"I was able to get the sniffer traces for both scenario's (with ether-channel) and without. Looking at the traces, with an ether-channel the Tsih value is always set to 0 from the MDS. When using just an access port, the Tsih value is returned with a non-zero value. My Cisco iscsi driver worked in both scenarios as it is a bit more lenient than your Qlogic. You noted on the case that you are using a QLA4010C iSCSI HBA."

thanks Arnel!

dayo

[aolabisi]

for the benefit of those following this string - Cisco engineers provided a workaround.

Use port channel number different from 1. I configured port channel 2 and it worked instantly.

dayo