User:Djgreen/Linux Administration

Rename Linux Boxes

If the machine is using dhcp I think you just need to switch in qip and reboot into the new lease / IP / hostname.

If the machine has a static configuration, you need to edit:

/etc/sysconfig/network-scripts/ifcfg-eth0

and

/etc/sysconfig/network

with the new values.

Try editing these files:

/etc/sysconfig/network

and

/etc/hosts

The hostname should be stored there.

After your box is on the network as the new name, run this command as root:

/usr/sbin/rhnreg_ks --force --activationkey <your_key_here>

Where <your_key_here> comes from the "activationkey" line in the web kickstart file. This will create a new "object" in red hat network.

Get Login Logs

in Linux, they have the /var/log/wtmp file but it is a binary file format. So the recommended interface is to use the last command.

last -n 100 will show the last 100 people who logged in.

You can also specify alternate wtmp files like

last -n 100 -f /var/log/wtmp.1

Controlling Access

It is possible to use pts groups to control access to Realm Linux.

cluster <cell> <PTS group>

is what goes in the config file. You can also hand edit /etc/update.conf if you don't want to re-install a box. It should look like this:

users blah XXXXXXXXXXXXXXXXXXXXXXXXXXX root blah XXXXXXXXXXXXXXXXXXXXXXXXXXX cluster> eos itecs-admin:helpdesk

where you replace the pts group with what group you want to use. If there is more than one pts group then you just add more cluster> lines.

Let us know if you need any further information. see also:

https://secure.linux.ncsu.edu/moin/Realm%20Linux%20Administrators%27%20Guide/Controlling%20User%20Access

Remote Reinstall of Existing RHEL box

(11:45:53 AM) gsgatlin: djgreen: You can edit /boot/grub/grub.conf and change the default boot item to re-install this workstation. (11:47:56 AM) gsgatlin: it starts numbering at 0 so if re-install is the first item it would be default=0, then you reboot and it starts installing.