New network's subnets

[enrico.nic]

Hi all

We have transferred to a new location two HP 9000, a D380 and a rp3410, both with HP-UX 11.11.
In the new building the network administrators have created some subnets, due to its (of the building) extension.
I have given the new static IPs,
172.18.0.100 (rp3410) and 172.18.0.101 (D380)
with 255.255.254.0 as subnet mask.
172.18.1.254 (last subnet's address) is the default gateway.

After this setting, both machines were invisible to/from outside their subnet.

I've decided to enable the "gated" daemon process, with a very simple configuration file, with just the "rip=yes" instruction and the statical definition of the default gateway.

This worked to enable network traffic on the D380, that now is reachable from the outside world and from other subnets in the same building; unfortunately, the rp3410 remains invisible from outside its subnet.

What am I doing wrong ? In terms of IP configurations, the two machines are now identical (obviously with 2 different IPs).
But from the rp3410, it seems that all routes outside its subnet are redirected to the host itself, as of this command:

# traceroute www.itrc.hp.com
traceroute to itrc.hp.com (192.6.72.228), 30 hops max, 40 byte packets
1 gissi.marionegri.it (172.18.0.100) 0.123 ms !N 0.058 ms !N 0.052 ms !N

Of course, all of the important processes are running on the rp3410 ...

Please help !

Thank you

Enrico

[Duncan Edmonstone]

Does the gateway : 172.18.1.254 respond to ICMP echo requests (pings). If not, then HPUX will think the router is down and stop sending data to it. You can stop this by turning of dead gateway detection:

ndd -set /dev/ip ip_ire_gw_probe 1

Make the change permanent across renoots by editing the file /etc/rc.config.d/nddconf (I think the format is self explanatory)

HTH

Duncan

[Duncan Edmonstone]

oops!

Of coure that should have been:

ndd -set /dev/ip ip_ire_gw_probe 0

Duncan

[Sandman!]

You are using private IPs which by definition are not routable. In order to make private IPs routable you need to use a gateway or router running NAT (network address translation) software. Ask your network administrators and they should be able to help you with that. Private IPs are invisible to the outside world and are routable only within the subnet. Check out URL below for relevant info:

http://www.faqs.org/rfcs/rfc1918.html

~hope it helps

[enrico.nic]

Thank you Duncan, I forgot to mention the ICMP "problem": the gateway is not responding to ping packets !
At http://docs.hp.com/en/B9901-90022/ch01s04.html there is a further explanation of the problem, where there is also a command that checks if the current gateway has beel flagged as "DEAD" from the system:
# ndd -get /dev/ip ip_ire_status | grep -e IRE_GATEWAY -e flag

The only thing that remains strange for me is that after giving the command that you pointed out,
# ndd -set /dev/ip ip_ire_gw_probe 0

the gateway continues to remain flagged as "DEAD".
I hope a reboot (I will do it this evening, now in Italy is 17:33) will solve the problem.
Until the reboot I will not close this issue ..

Thank you all

Enrico

[Matti_Kurkela]

I had a similar problem a while ago.

Reboot will certainly restore a gateway that is flagged "DEAD" to working state... IF you have the ndd setting in /etc/rc.config.d/nddconf.

But a reboot is a bit of an overkill: just removing and re-adding the default gateway after setting the ip_ire_gw_probe setting to 0 would be sufficient.

MK

[enrico.nic]

Thank you all for the answers, the reboot solved the problem.

Enrico

[enrico.nic]

Thank you