Linux network

If you have configured your network adapter to use DHCP, then the protocol will do a broadcast on the network to ask for an IP address. It is up to the DHCP server to give it. You can see what your adapter is configured to in /etc/sysconfig/network-scripts/ifcfg-eth0 on RedHat ( and other distributions ). If BOOTPROTO=dynamic then you use DHCP, if its = Static then you use fixed IP.

Thank you very much. Just one more question. What do I type at the command prompt to get to find out the information if BOOTPROTO=dynamic.?

try cat /etc/sysconfig/network-scripts/ifcfg-eth0.

I am trying it now and will get back to you smart and helpful jazzjack.

I get BOOTPROTO=none. Are the ips dynamic or static? If they are static what do I type on the command line to find out the ip?

The easiest way is proberly to run /usr/bin/redhat-config-network

did redhat-config-network solve your problem?

I'll check and get back with you magical jazzjack.

I'm running CentOS release 4.2 and there is not a /usr/bin/redhat-config-network file but there is
/usr/bin/system-config-network. It is a symbolic link to /usr/bin/consolehelper and when I run
/usr/bin/system-config-network it is a GUI interface that asks to configure the system.

Well basically it is the same application. The main thing is that you can configure the network. :-)

The user explained today that his screen was hung and couldn't do anything but turn it off.

To check the ip on your local client, from shell: ifconfig

To check your external ip, from browser: http://www.myip.dk/

To renew the ip from the dhcp server, from shell:

dhcpcd or dhclient

Well if BOOTPROTO=none, then the interface is not configured to get an IP. If you can't change the file manually (/etc/sysconfig/network-scripts/ifcfg-eth0), then you must use an utility like system-config-network.

Why the user got stuck in the config console...Well can't give you a good answer on that one. I assume that the user ran the script as root.Right?

/jazz

I'll find out.

I can change BOOTPROTO in /etc/sysconfig/network-scripts/ifcfg-eth0. Do I type small or capital letters and do a make? Then what do I type as a command to get the dynamic ip address?

BOOTPROTO=dhcp

You dont need to do make. Just restart your network or boot the server.

How do I restart my network? Will anyone notice? People are on the server night and day.

I'm a little puzzled here... There is no IP on your LAN interface, and yet people are on the server day and night???

If this is a secondary interface then you can try:
cd /etc/sysconfig/network-scripts
./ifup eth1      (That is if it is eth1).

There is an ifdown script aswell.

If it is the primay network interface, then you have a problem.