we have implement a 2 node nw 6.5 cluster by one of our customer.
Both nodes have 2 Qlogic 2300 HBAs an are connected over 2 Qlogic SANbox
Fibre Channel Switches to an ACER S700 FC Storage.
Clustering works fine.
Just now, we have implement a second SAN Storage (same as above) for
redundancy, the storage are connected to both Fibre Channel Switches. We are
enable NSS Mirror on the Primary Storage - it works - no Problems BUT:

- when the customer get or put large files (ZEN Images) to or from the
Storage, both nodes get a poisen pill.
- when the customer make a backup (arcserve 11.1) on of the nodes get a
poisen pill

When we disable the NSS Mirror, all function works fine!

any ideas?