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SP2 machine with 2 Network Interfaces: How do I control the data transfer between the two interfaces?

Technote (FAQ)


Problem: Installing and running a new file server on a node of an SP2, we noticed the following problem:

This node has 2 network interfaces running, 1 Token Ring for production, and a Standard Ethernet for specific communications between this node and the Control Work Station of the SP2 .

After creating a volume, and doing a 'vos exam' of this volume, we noticed that the information contained in the volume header (The second line in fact) was relative to the Ethernet Interface instead of the Token Ring, that is to say the File server was known through the ethernet interface.

1) Does that mean that data will transfer through ethernet instead of token ring (the target is to transfer data through token ring, ethernet being an interface for service use...)?


With multi-homed fileservers, here is some information on what adjustments may be made to eliminate traffic on certain interfaces.

Standard AFS accesses can be funneled to one interface by using `fs setserverprefs' in the rc script of the client machines. The primary interface can be set to a low numerical rank and the other interfaces can be set to very high numerical rank. The rank is an integer in the range from 1 to 65,534. The `fs setserverprefs' needs to be run in the startup script in this case, because the client machine stores this information in the kernel and it is recalculated when the machine is rebooted.

To control the traffic from the fileserver back to the client, the fileserver will always use the first interface it encounters to communicate with the clients (and database servers to communicate with other processes). This means that the first network interface
that is listed is the one we will use. So, you need to modify your startup on the fileserver to start your preferred card first and then any other cards. In this way, the preferred card will be the first listed in an 'ifconfig' (or equivalent) and will be the one used when the fileserver talks to the clients.

Historical Number


Document information

More support for: AFS

Software version: 3.6

Operating system(s): Platform Independent

Software edition: All Editions

Reference #: 1047009

Modified date: 20 February 2010