Quote Originally Posted by Laxity
[...] The main focus is High Availability..

So afaik we should interconnect the DSS boxes with two ethernet cables.
The DSS boxes would additionally have (each) one connetion to the dedicated switch where the two Xen Sever will be connected to for this setup.

The virtualisation boxes are simply connected trough one ethernet cable to the main switch.

Is this okay? Do we need more cables? More NICs?

Would it be wise to use a second switch for fault tolerance? If yes, how many NICs would we need on the boxes? We want to have the best HA experience possible in this setup..

Thanks a lot in advance!
Hi Laxity,

if your trying to run a fully separate "SAN network" and are looking for full redundancy, you should IMO go for (at least) four Ethernet ports for each Xen server - two redundant ports to redundant switches for the SAN network and two redundant ports (again to redundant switches) for the client-side network... plus, optionally, a management port per server (to separate VM traffic from Xen server management traffic).

HA means to avoid single points of failure - so if the connection from the Xen servers to the DSSes are only through the "dedicated switch", then that switch is a SPOF.

Do you plan to connect the "dedicated switch" to the rest of the network? Then you might be able to handle link failures through that path.

Do you plan to run the Xen servers as a "cluster", with every VM runnable on both servers (take.over in case one of the Xen servers fails)?

How important is *access* to the VMs? You might need to provide redundant access paths to your Xen servers (from the client's point of view).

How do you define "available"? Is it ok to run all VMs on a single node - ie in case that the link from the client net to one of the Xen servers fail? Does your take-over rule set permit handling such an event?

With regards

Jens