topic Re: can not ping in same segment in Operating System - HP-UX

can not ping in same segment

Jack Fan — Thu, 11 Nov 2004 22:46:31 GMT

I have a strange networking problem,
Here, I have 3 servers and ip as below,

server 1 : 10.37.36.101
server 2 : 10.37.36.50
server 3 : 10.37.36.107

OS version is 11i in all servers, and have secondary NIC card for IP 175.159.2.xxx in all servers for data backup.

I have done some testing and result as below,

1) 10.37.36.101 ping 10.37.36.107 -->ok
2) 10.37.36.101 ping 10.37.36.50 -->ok
3) 10.37.36.50 ping 10.37.36.107 --> failed.
4) 10.37.36.50 ping 10.37.36.101 --> ok
5) 10.37.36.107 ping 10.37.36.50 --> ok.
6) 10.37.36.107 ping 10.37.36.101 --> ok.

why the 10.37.36.50 ping 10.37.36.107 failed?

then I have do testing traceroute on 10.37.36.50

1) traceroute 10.37.36.107 -> failed
2) traceroute -i lan1 10.37.36.107 -> ok

Thanks,

Re: can not ping in same segment

Steven E. Protter — Thu, 11 Nov 2004 22:58:59 GMT

It depends.

check /etc/rc.config.d/netconf

make sure the netmask is the same.

Make sure ipfilter firewall is not running blocking ping.

Make sure network switch port configuration is set to manaul for 100 BaseT and below and auto negotitate if 1000 BaseT.

run cstm mstm or xstm and make sure the network card is working right.

dmesg output might be useful in diagnosis as well.

SEP

Re: can not ping in same segment

Steven E. Protter — Thu, 11 Nov 2004 23:05:25 GMT

Few other things come to mind:

make sure there is no other machine on your network with the ip addy 10.37.36.107.

Make sure in netconf there are no virtual ip addresses equal to: 10.37.36.107

Make sure the machine in question does not have two nic cards on the same subnet.

hp-ux does not support that.

example

192.168.0.30 mask 255.255.255.0

network is 192.168.0
You can not have a second NIC card on that network. It will crash networking or cause th very problem you report.

SEP

Re: can not ping in same segment

Jack Fan — Thu, 11 Nov 2004 23:38:00 GMT

I have solved the problem, root cause is there is incorrect routing table on 10.37.36.107 server...

Dest/Netmask Gateway Flags Refs Use Interface Pmtu
127.0.0.1 127.0.0.1 UH 0 214 lo0 4136
10.37.36.51 10.37.36.51 UH 0 237 lan3 4136
175.159.2.207 175.159.2.207 UH 0 0 lan1 4136
10.37.36.107 10.37.36.107 UH 0 31944 lan2 4136
10.37.36.0 10.37.36.107 U 2 0 lan2 1500
175.159.2.0 175.159.2.207 U 2 0 lan1 1500
127.0.0.0 127.0.0.1 U 0 0 lo0 4136
default 10.37.36.254 UG 0 0 lan2 1500

please see 10.37.36.51

but no NIC card for 10.37.36.51 on 10.37.36.107 server..

Name Mtu Network Address Ipkts Opkts
lan2 1500 10.37.36.0 10.37.36.107 615820 754669
lan1 1500 175.159.2.0 175.159.2.207 0 0
lo0 4136 127.0.0.0 127.0.0.1 214 214

Thanks,

Re: can not ping in same segment

Anil C. Sedha — Mon, 15 Nov 2004 18:34:29 GMT

Jack,

hope this helps you as below

tracert 10.37.36.107 (where does it fail. does it go upto the router .. probably 10.37.36.1)

then,

route add 10.37.36.107 10.37.36.50 (adding a route from your server that is not pinging.

Let me know what happens. Since it is already pinging from the other server you will not have to perform add route there.

-Willy(Anil)

Re: can not ping in same segment

Anil C. Sedha — Mon, 15 Nov 2004 18:35:31 GMT

ignore my message. sent before reading your last reply.