Actually, what the poster is asking about does not require a shared
file system, merely server clustering and shared LUN access.

As an example, you can use Veritas Cluster Server (VCS) and Veritas
Volume Manager to manage what you're asking. What I do is mirror with
VM and setup VCS to import the mirror as rw in case of failover.

Given your question though you would not even need to mirror since you
can access the same LUN if the host mounts it ro. It would look
something like this:

Host A - mounting LUN1 as rw. primary host for LUN1
Host B - mounting LUN1 as ro, failover host for LUN1

If Host A barfs Host B re-mounts LUN1 as rw. Where the scripting
takes place really depends on how you're failing over. Is it custom
scripts or commercial package. Either way I guess something triggers
Host B to re-mount LUN1.

~F

On Mon, 20 Oct 2003 02:53:31 -0700, "nospam"
wrote:

Hi,
In a SAN enviornment, can two servers have access to the same storage device
at the the same time?
I want to implement a failover, one server doing all the writing, the other
only read from the disk. If one server goes down, the other will do both.
Is this possible and normal way to use SAN?

Where do you configure this, on server, storage or switch?
Thanks