ISCSI 2 node questions

[Wubbalubbadub]

Ok,

 

Forgive my ignorance on this.

 

Basically I am trying to get planned a new 2 node Hyper V cluster.

 

The 2 nodes will have each; Dell R820

 

64 cores

256GB RAM

Quad NIC

Redudent PSU

 

 

 

And a SAN:12 x 900GB 10SAS - dell MD3220i ISCSI SAN

 

So now my question is...

 

Obviously the nodes have 4 network ports on them with the quad NIC... Now do I need to do scenario 1 or 2....

 

1) Vlan 3 of the ports per server connecting them to a switch, with the ISCSI san going into the same switch.

- Use the last remaining port for network traffic...

 

2) Get a ISCSI card which I can connect the 2 nodes to the SAN directly and then use the 4 ports for general network traffic.

 

Look forward to your inputs.

 

Matthew

[Wubbalubbadub]

Can i do a little bump on this?

[kmount]

Hi Matthew,

 

If I was building a system like this I would have a pair of dedicasted iSCSI nic's (at least) split over a pair of resilient switches so you can survive a switch failure.

 

The MD3220i should have ports on each controller connected to each switch so it too can survive a switch/nic failure. -- If you don't have a resilient switch configuration in place for this it's less relevant I suppose.

 

Given the choice; in your case looking at the size of the boxes and future expansion potential I would buy another network card and run 1x iSCSI from each card (so you can survive nic failure) using MPIO (not teamed) and then have a dedicated management network (I'd team a port from each physical nic onto this) and then that leaves you 4 ports for the main LAN connection (again, split over the two physical NICs for resilience).

 

If you're pushed for ports you could merge the management network into the LAN network (VLAN separate them); and if pushed further you could VLAN the Mgmt, LAN, and iSCSI networks on top of the same physical links but you may have hassles with this with iSCSI residing on top of the team being discouraged in best practice (how much you'd notice on a small system like this is up for debate though).

 

In either case, I can't imagine you'd flatten the network links with just the two hosts talking to the SAN so whichever way you go should be fine.

 

Couple of iSCSI specific bits; make sure you have the multipath i/o feature installed & make sure your iSCSI VLAN supports Jumbo Frames you'll probably want to evaluate their use in your environment. (some people say to use them, some say don't ; MS best practice says to use them)

 

Worth a read - Windows Server 2012 Hyper-V Best Practices (In Easy Checklist Form) - Ask Premier Field Engineering (PFE) Platforms - Site Home - TechNet Blogs

 

 

(PS; I'm more of a VMware guy so my knowledge here is largely field/crowd sourced)