MDR redundant FC connections

[Bas Kokken]

I am investigating possibilities to have the MDR device connected to two redundant switches. Is this possible? The reference manual describes only the usage of loadbalancing with a dual FC module, not the usage of fail-over when a FC switch or HBA fails.
The switches and MDR are used by a Windows NT4 cluster and a Windows 2000 Server, storage on a RA4000 and a RA4100 disk cabinet.

[Uwe Zessin]

Bas,
as far as I know, OpenVMS is the only operating system that can do a tape path failover between the MDR's ports.

[Peter Mattei · Accepted solution]

In order to do that NT would have to be able to identify an map redundant pathes to a tape drive. Most OSes including NT cannot do that.
If you would connect your router with 2 pathes to your NT server each tape drive would be seen twice with 2 different SCSI adresses. You would not really want that.
You have to make sure that you only see the drive once per server.

BTW. NT shows the same behaviour with disks. To overcome that you need multpathing SW like SecurePath. Unfortunately there is no SecurePath SW for tape available to date!

Cheers
Peter