topic Re: routing problem in Operating System - HP-UX

routing problem

Sprint Unix Team — Mon, 30 Apr 2001 13:57:45 GMT

I can ping individual IP address from a machine. But when I try to ping the whole network, it returns response only from a particular machine. Also, I cant talk to some machines on the same lan. The netconf file and routing tables are all identical. Can somebody help???

Re: routing problem

Vincenzo Restuccia — Mon, 30 Apr 2001 14:12:09 GMT

firewall rules?

Re: routing problem

Sprint Unix Team — Mon, 30 Apr 2001 14:27:25 GMT

Nopes these lans are on the inside of the firewalls. So I dont think firewall is a issue here.

Re: routing problem

Patrick Wallek — Mon, 30 Apr 2001 14:32:34 GMT

Are you using the correct broadcast address to ping the whole network? Is there a machine, router, etc. that inadvertantly has the address?

Can you give an example of the output you are getting?

Re: routing problem

Sprint Unix Team — Mon, 30 Apr 2001 15:01:29 GMT

Patrick,

This is the output i get;
carbon.sci-isg.com#ping 10.12.107.0
PING 10.12.107.0: 64 byte packets
64 bytes from 10.12.107.168: icmp_seq=0. time=2. ms
64 bytes from 10.12.107.168: icmp_seq=1. time=0. ms
64 bytes from 10.12.107.168: icmp_seq=2. time=0. ms

Re: routing problem

Richard Darling — Mon, 30 Apr 2001 15:14:21 GMT

your ping response indicates that there is only one machine logged into the network? what machine is the 168 address? yours?

Re: routing problem

Sprint Unix Team — Mon, 30 Apr 2001 15:30:54 GMT

Richard,

Thats the issue I have. I get response only from one machine which is on the network. Its not my machine. Also there are other machines on the network when I ping them individually i get a response but not when I ping the network.

Re: routing problem

Patrick Wallek — Mon, 30 Apr 2001 16:22:39 GMT

I think you are using the wrong address as your broadcast address to ping the whole network. Do an 'ifconfig lan?' on your NIC and see what the broadcast address is set to.

Here's a sample from my machine:

# ifconfig lan1
lan1: flags=863
inet 172.30.1.88 netmask ffff0000 broadcast 172.30.255.255

My broadcast is 172.30.255.255 and if I ping to that address then I get a response from the whole network (at least I think, I haven't counted. I do get a response from more thing one machine though.).

I just tried 'ping 172.30.0.0' as well and it worked too. Now I'm confused........

Re: routing problem

MANOJ SRIVASTAVA — Mon, 30 Apr 2001 16:52:03 GMT

Check this out , in case you are having doubts that whetehr there are two machine susing the same ip then disconnect the one you know then try pinging it , incase you get a response then there two machine using the saem IP address .
Also it looks the default router is not setup correctly in case you have problems acroos the network.

Manoj

Re: routing problem

Celso Medina Kern — Thu, 03 May 2001 16:51:07 GMT

Hi,

It seems to be due to different subnetmasks among these systems. If not, it is a really weird behaviour. I would like to see output of these commands:
netstat -in
netstat -rn
lanscan
arp -a
ifconfig lan? # < 1 command for each lan;
And your network map.

Re: routing problem

Juan González — Fri, 04 May 2001 11:12:58 GMT

Hi,
there is a parameter for the network device /dev/ip that indicates when to repond to echo broadcast.
If you have HPUX 11.x (or Solaris) you can get this parameter using
#ndd /dev/ip ip_respond_to_echo_broadcast

and set it to 1 (true), if you needed, using
#ndd /dev/ip ip_respond_to_echo_broadcast 1

if you have HPUX 10.20 you must do
#nettune icmp_mask_agent

and to set it
#nettune -s icmp_mask_agent 1

Best regards