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Redhat 9 ntl cable modem dhcp problems

I previously had this working under RH8 but since installing RH9 (on dual boot machine with XP) I have problems both with USB and Cat5 conection (both OK under XP)

Specifically, I get corect IP address asingned to eth0 (or eth1 if usb) but then I can not ping or attach to anything. Have copied most settings from RH8 but same result.

If I specify Gateway IP address and run "route add default eth0", I can then ping gateway, but not nameservers. (nameservers are specified in resolve.conf)

I notice that pump is not included with RH9 but is still refered to in /sbin/ifup. Also in RH8, I had a load of lease stuff in /etc/dhcpc directory, but this directory is not even present under RH9.

Should I try to install pump and add DHCP_PROG=/sbin/pump ?
Any other sugestions or details required ?

RedHat is always making changes.
I suggest using the RedHat Network Configuration GUI
Type: redhat-config-network

You may need to restart the network.
Type: service network restart

Mathieu

Thanks for the reply, but I have lost count of the number of times that I have re-started the network service and run redhat-config-network. I deleted all config files and the device and re-installed from scratch last night, but same result: correct IP address is obtained but then Network unreachable, can not even ping numerical IP address. I'm going to try installing Pump and if that fails I think I'll go back to RH8

It may be a routing problem.
Take a look at your routing table:

Code:

route -n

Mathieu, thanks again,

Here's some output from route -n and some other commands

Code:

route -n

Kernel IP routing table

Destination    Gateway        Genmask        Flags Metric Ref    Use Iface

213.105.253.0  0.0.0.0        255.255.255.0  U    0      0        0 eth0

169.254.0.0    0.0.0.0        255.255.0.0    U    0      0        0 eth0

127.0.0.0      0.0.0.0        255.0.0.0      U    0      0        0 lo

Code:

ifconfig



eth0      Link encap:Ethernet  HWaddr 00:80:5F:B7:37:BC  

          inet addr:213.105.253.227  Bcast:255.255.255.255  Mask:255.255.255.0

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:9297 errors:0 dropped:0 overruns:0 frame:0

          TX packets:7 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:100 

          RX bytes:435228 (425.0 Kb)  TX bytes:994 (994.0 b)

          Interrupt:11 Base address:0xc800 Memory:e0000000-e0000038

If I ping any IP address i get:

Code:

connect: Network is unreachable

but if I run

Code:

route add default eth0

then when I ping any IP address i get

Code:

From 213.105.253.227 icmp_seq=1 Destination Host Unreachable

BUT if I ping the gateway I now get a normal response.

Hope some of this helps someone to suggest a few things to try!:scratch:

You are missing the default gateway to your ISP.
There should be a fourth line with the Gateway column set to 213.105.253.1 (or 213.105.253.254).

If you want to add it manually, use the following syntax:

Code:

route add default gw my_ISP_gateway

You can also try to add it to the eth0 configuration file (/etc/sysconfig/network-scripts/ifcfg-eth0).

Runing

Code:

route add default gw 213.105.226.254

gives me

Code:

SIOCADDRT: Network is unreachable

OK

Thanks Mathieu for trying to help, I'm typing this in RH9, as all of a sudden it started working with just the same basic settings that I started with. I found a forum (nthellworld.com) where several users form my area had been reporting wierd problems over the last few days - so it seems that problem was at the ISP end all the time. Why it worked with XP and not RH9 I will probably never know.