Routing problem on HP-UX

[Julián Rodríguez Aragón]

Please, if you have the time and the knowledge, have a look at the attached PDF document and tell me how I should I set up a route on the â vpar2â HP-UX host that allows it to communicate with the â hpoo72â Windows hosts.

In the document, youâ ll see another Windows host, called â julianvmâ , that is able to communicate with both â vpar2â and â hpoo72â , thanks to a persistent route to the 10.30.0.0 network, with netmask 255.255.0.0, via the gateway on 10.0.0.7 with metric 1.

I wanted to achieve the same behavior on HP-UX, and have tried the following commands with no success:

# route add net 10.30.0.0 netmask 255.255.0.0 10.0.0.7 1
# route add net 10.30.0.0 netmask 255.255.0.0 10.0.0.200 1
# route add net 10.30.0.0 netmask 255.255.0.0 10.30.0.2 1
# route add net 10.30.0.0 netmask 255.0.0.0 10.30.0.2 1
# route add net 10.30.0.0 netmask 255.0.0.0 10.0.0.200 1

Thank you in advance,
Julián

[Laurent Menase]

in fact only one route is needed on your vpar2

route add net 10.30.0.0 netmask 255.255.0.0 10.0.0.200 1

[Julián Rodríguez Aragón]

As I said, I've tried what Laurent suggested.

Still I'm not able to ping ...

vpar2.nsbc.compaq.es.root => netstat -rn
Routing tables
Destination Gateway Flags Refs Interface Pmtu
127.0.0.1 127.0.0.1 UH 0 lo0 32808
10.20.0.53 10.20.0.53 UH 0 lan0 32808
10.0.0.0 10.20.0.53 U 2 lan0 1500
10.30.0.0 10.0.0.200 UG 0 lan0 1500
127.0.0.0 127.0.0.1 U 0 lo0 32808
default 10.0.0.7 UG 0 lan0 1500

vpar2.nsbc.compaq.es.root => ping 10.30.2.101
PING 10.30.2.101: 64 byte packets



----10.30.2.101 PING Statistics----
16 packets transmitted, 0 packets received, 100% packet loss

[Laurent Menase]

you should then try to get a nettl trace at IP and interface level. and check where your ping is sent to.
You can also check at ip_ire_hash
( ndd -get /dev/ip ip_ire_hash)

[Duncan Edmonstone · Accepted solution]

I suspect the windows systems only work cos the IP stack on MS windows is completely bogus... looking at your configuration, to me this is a comnpletely invalid network setup

If you have a 10.0.0.0 network with a subnet mask of 255.0.0.0 then the 10.30.0.0 subnet is actually just part of the 10.0.0.0 network, so as HP-UX correctly interperts the rules in the RFCs around routing, anything for the 10.30 network is just going to be thrown out of the interface with address 10.20.0.53 as HP-UX is assuming (correctly according to the RFCs) that anything with a 10.30 address is on the same subnet.

You could *try* adding a route just to the host rather than to the subnet and that *might* work (can't remember the order that these things are checked in), try something like:

route add 10.30.2.101 10.0.0.200 1

But I wouldn't be surprised if that doesn't work either.

Remember its the windows hosts that are "broken" here, by allowing this invalid IP subnet configuration to work in the first place.

HTH

Duncan

[Julián Rodríguez Aragón]

A colleague of mine, Angel Garcia, did the magic by adding the following route on HP-UX:

# route add host 10.30.2.101 10.0.0.7 1

I forgot to say that 10.0.0.7, besides of being the default gateway, also has a route created that allows to reach network 10.30.0.0 via 10.0.0.200 interface.

Cheers,
Julián

[Jeroen Peereboom]

Nevertheless, Duncan is right. You should redesign your network, especially the subnet masks.

JP