Clarifications on iSCSI in ESX 3.5

[mattjk]

I'm hoping someone can clarify a few points regarding iSCSI in ESX Server 3.5 for me.

I've learnt a hell of a lot from reading old posts for the past few hours, but there are a couple of points about which I'm still unsure due to lots of conflicting information :-S

Multi-pathing:

- I understand that ESX 3.5's iSCSI software initiator does not support multi-pathing (only failover), but what about with an iSCSI HBA? Does the use of an iSCSI HBA allow true active-active multi-pathing for ESX 3.5?

Fail-over & redundancy:

- Can you achieve switch redundancy with ESX 3.5's iSCSI software initiator? That is, connect multiple iSCSI NICs in the server to different switches, to guard against switch failure? Or is it only possible to provide NIC redunancy (by teaming multiple NICs to the one physical switch)?

- Is there any redundancy benefit in using two 1-port iSCSI HBAs vs one 2-port HBA? Card failures and the like.

Jumbo Frames:

- Similar to the above question, but regarding jumbo frames: the ESX 3.5 iSCSI initiator doesn't support jumbo frames, but what about with an iSCSI HBA? Does the use of an iSCSI HBA allow jumbo frame support?

SAN Support:

- Quite a few of the lower-end SANs listed on the ESX 3.5 HCL - for example the NetApp FAS2000 series - show support in the "iSCSI software initiator" column but not in the "iSCSI hardware initiator" column. Just to confirm, does that mean these SANs will work with ESX 3.5's iSCSI software initiator, but not with a HBA (like the QLogic cards)?

Thanks everyone, greatly appreciate any assistance.

[sthoppay_wipro]

Multipathing:

iSCSI HBA act like FC HBA, so, it is similar to FC HBA support.

Fail-over & redundancy:

Need to look into the switch information. But, my feeling is yes, you can connect to two different switches.

regarding two 1 port iSCSI HBA vs one 2 port HBA, one protects from card failure. but it eats the slot.

Jumbo frames:

Yes, iSCSI HBAs support jumbo frames. But, I haven't seen any big advantage of using jumbo frames.

San Support:

It will work. But, was never tested & certified might be.

[mattjk]

Thanks very much for the info.

A couple of small clarifications:

iSCSI Multipathing - "iSCSI HBA act like FC HBA, so, it is similar to FC HBA support."

So is that a yes to multi-pathing support via an iSCSI HBA?

SAN hardware iSCSI initiator support - "It will work. But, was never tested & certified might be."

So that basically means no support provided by VMWare?