5.3 diskless PC & 2 NICs: Can I separate NFS from other network trafic?

[Rob]

Hello,

I have a master for a cluster of diskless slaves; the master
serves the slaves over NFS (/, /usr, /home). I have two
internet cards in all PCs, but only using one on the slaves
right now.

Could I use the second internet card to separate the NFS trafic
from all other network trafic? At the moment, I have this on a
slave:

   rl0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         options=8<VLAN_MTU>
         inet6 fe80::2a0:b0ff:fe0e:3a95%rl0 prefixlen 64 scopeid 0x1
         inet 192.168.123.1 netmask 0xffffff00 broadcast 192.168.123.255
         ether 00:a0:b0:0e:3a:95
         media: Ethernet autoselect (100baseTX <full-duplex>)
         status: active
   rl1: flags=8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
         options=8<VLAN_MTU>
         ether 00:50:fc:e9:30:49
         media: Ethernet autoselect (100baseTX <full-duplex>)
         status: active

The master is 192.168.123.254, which is also the router to this local
network (so the master has one NIC connected to the Internet, the other
to the switch of the local network).

How can I utilize the dual NIC setup on the slaves in a optimal way?

Thanks,
Rob.