Perhaps, I wasn't clear in my message, I'd rather have NetBackup  
control this, that's being somehow associate these interfaces with
a storage unit, in some pseudo way, so I can re-build my NetBackup
classes based on subnet and assign a storage unit.  A clean way
to do this, I suppose.

As for the routing issues/options I'm aware of these.  Thanks.

-ravi

On Mon, 16 Oct 2000, Buddy Lumpkin wrote:

>Solaris 2.6 will actually round-robin its interface usage if more than one
>is found to have the same metric and that metric is the lowest route to the
>destination. I remember having to disable this functionality because it was
>screwing up the firewall when I was at The Seattle Times.
>
>The Kernel Parameters are something like enable_group_ifs and I beleive
>enable_strict_dst_multihoming.
>
>something like that.
>
>--Buddy
>
>
>-----Original Message-----
>From: Joshua Fielden [mailto:jfielden AT excitecorp DOT com]
>Sent: Monday, October 16, 2000 11:50 AM
>To: Andrew Steingruebl
>Cc: Ravi Channavajhala; veritas-bu AT mailman.eng.auburn DOT edu
>Subject: Re: [Veritas-bu] Network load balancing
>
>
>On Mon, Oct 16, 2000 at 01:36:16PM -0500, Andrew Steingruebl filled up my
>inbox with:
>> 
>> Ravi Channavajhala said:
>> 
>> >Is it possible to do network load balancing across several
>> >physical interfaces in a media server i.e., one storage
>> >unit being shared by several netbackup slave server
>> >definitions eg., backup-e0, backup-e1, backup-e2?  The
>> >primary definition is backup (nodename).  All these interfaces 
>> >are on different subnets.  The storage unit is defined for
>> >backup instance only.
>> >
>> >I already defined these in bp.conf on the master as well as
>> >the slave.  What I dont understand is, how does the master
>> >make a determination to direct a specific backup stream to
>> >a specific network interface.  Thanks.
>> >
>> 
>> There are 2 streams of traffic for each client.
>> - backup stream
>> - catalog stream
>> 
>> A server will automatically talk to another machine using the interface
>with 
>> the best metric. On Unix, if you've got 2 interfaces, the system will use
>the 
>> interface on the network its trying to reach.
>> 
>
>If only this were true for every platform. On Solaris, this is not the truth
>in practice. Also, if you have an environment like we have, with 11
>interfaces trying to take 'least hop' to 30 changing VLAN's, you know that
>static routing is not a scalable solution, nor is 30 interfaces in a
>machine.
>
>> The client will need to know about each server name.  So, what you
>probably 
>> want to do is:
>> 
>> 1. Set up multiple "A" records/IP's for your master server.
>> 2. Set up 1 storage unit and makes it owned by whatever interface name you
>
>> consider primary.
>> 3. List all of the "aliases" for the master server in the bp.conf file on 
>> master and slaves.
>> 
>> All backup traffic will take the optimal route. All catalog traffic must
>get 
>> sent to "master" which is the top line in the bp.conf file.
>> 
>> You will have asymmetric traffic flows, but your backup data will tape the
>
>> optimal route.
>> 
>
>And if data goes up one interface, and down another for any reason (router
>failure, hsrp kicks in, different path is taken...), the software recovers
>less than gracefully. 'Chokes' is a better term.
>
>With that said, it Does The Right thing(tm) most of the time, just not all
>of the time, and not as simply as stated.
>
>