28.7. Post-installation Script

28.7. Post-installation Script

You have the option of adding commands to run on the system once the installation is complete. This section must be at the end of the kickstart file and must start with the %post command. This section is useful for functions such as installing additional software and configuring an additional nameserver.


If you configured the network with static IP information, including a nameserver, you can access the network and resolve IP addresses in the %post section. If you configured the network for DHCP, the /etc/resolv.conf file has not been completed when the installation executes the %post section. You can access the network, but you can not resolve IP addresses. Thus, if you are using DHCP, you must specify IP addresses in the %post section.


The post-install script is run in a chroot environment; therefore, performing tasks such as copying scripts or RPMs from the installation media do not work.


Allows you to specify commands that you would like to run outside of the chroot environment.

The following example copies the file /etc/resolv.conf to the file system that was just installed.

%post --nochroot cp /etc/resolv.conf /mnt/sysimage/etc/resolv.conf
--interpreter /usr/bin/python

Allows you to specify a different scripting language, such as Python. Replace /usr/bin/python with the scripting language of your choice.

28.7.1. Examples

Register the system to a Red Hat Network Satellite:

          %post ( # Note that in this example we run the entire %post section as a subshell for logging. wget -O- http://proxy-or-sat.example.com/pub/bootstrap_script | /bin/bash /usr/sbin/rhnreg_ks --activationkey=<activationkey> # End the subshell and capture any output to a post-install log file. ) 1>/root/post_install.log 2>&1

Run a script named runme from an NFS share:

          mkdir /mnt/temp mount -o nolock /mnt/temp open -s -w -- /mnt/temp/runme umount /mnt/temp


NFS file locking is not supported while in kickstart mode, therefore -o nolock is required when mounting an NFS mount.

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