routing issues with multiple NIC cards

UNIX HP-UX
1

I am running HP_UX 11.23 with 4 NIC cards (this is our TSM server)
I have 4 subnets we are backing across. trying to keep traffic on their subnets. I only have one route statment should I add more.
route add net 123.99.8.0 netmask 255.255.255.0 123.99.8.254
route add net 123.99.67.0 netmask 255.255.255.0 123.99.67.254
route add net 123.99.65.0 netmask 255.255.255.0 123.99.65.254

# ifconfig lan0
lan0: flags=1843<UP,BROADCAST,RUNNING,MULTICAST,CKO>
inet 123.99.3.234 netmask ffffff00 broadcast 123.99.3.255
# ifconfig lan1
lan1: flags=1843<UP,BROADCAST,RUNNING,MULTICAST,CKO>
inet 123.99.67.234 netmask ffffff00 broadcast 123.99.67.255
# ifconfig lan2
lan2: flags=1843<UP,BROADCAST,RUNNING,MULTICAST,CKO>
inet 123.99.65.234 netmask ffffff00 broadcast 123.99.65.255
# ifconfig lan3
lan3: flags=1843<UP,BROADCAST,RUNNING,MULTICAST,CKO>
inet 123.99.8.234 netmask ffffff00 broadcast 123.99.8.255

# netstat -nr
Routing tables
Destination Gateway Flags Refs Interface Pmtu
127.0.0.1 127.0.0.1 UH 0 lo0 4136
123.99.3.234 123.99.3.234 UH 0 lan0 4136
123.99.8.234 123.99.8.234 UH 0 lan3 4136
123.99.65.234 123.99.65.234 UH 0 lan2 4136
123.99.67.234 123.99.67.234 UH 0 lan1 4136
123.99.3.0 123.99.3.234 U 2 lan0 1500
123.99.67.0 123.99.67.234 U 2 lan1 1500
123.99.65.0 123.99.65.234 U 2 lan2 1500
123.99.8.0 123.99.8.234 U 2 lan3 1500
127.0.0.0 127.0.0.1 U 0 lo0 0
default 123.99.3.254 UG 0 lan0 0

2

Have you filled correctly /etc/rc.config.d/netconf file?
After the stanzas for your multiple lans, there is another section
for all the routings for EACH lan you have (lan[0] [1] etc) you will have to copy the block and configure for each lan interface if not yet done...

3

You do not need special routes for these. They get automatically created when you add the interface.

Think about it.. how do I get to the 12399.8.0 net, I go out the 123.99.8.234 interface.

The only route that counts in your config is the default going down 123.99.3.234 interface

If traffic from some other net ( e.g 192.168.4.1 )comes in on the 123.99.8.234 net it will be returned to the router via the 123.99.3.234 LAN unless you add a statement like this.

route add 192.168.4.0 123.99.8.254 1

It is the extranets you want to set the routes for. Same nets will always go out the proper LAN and get routes added automatically as part of ifconfig.