This KB explains the steps needed to be done for a new Xen server installation.

We assume that the Xen server needs connection to iSCSI disk and the following steps have to be done before attaching iSCSI disk.

At least two physical connections are required

1- Connection to access switch (This must NOT be a SAN switch)

2- Connection to SAN switch.

1- The switch port is in Internet VLAN (untagged VLAN ID 10 or 11) for Internet access. This is the only interface that is configured during the installation. The rest of configuration are done after the Xen server is added to XenCenter.

2- The switch port is in SAN (untagged VLAN ID 2). The hypervisor interface configuration has to be done through Xen Center. Change the MTU to 9000 (Jumbo).

3- Configure SAN2 (VLAN ID 2002) in XenCenter and add the interface to the hypervisor.

For more details about steps 2 and 3 see the following KB.

This KB is relevant:
How to configure VLANs for Xen VMs in XenCenter