The following message may appear when you are updating a 2.4-1 system to the new Version 2.4-2:
Space on /var/cache/apt/archives: OK
ERROR: Not enough space in /boot, need at least 50 MB. This may interrupt the update and result in an inconsistent system!
If neccessary you can skip this check by setting the value of the baseconfig variable update24/checkfilesystems to “no”. But be aware that this is not recommended!
This message indicates that there is insufficient free space available in the /boot directory on the hard drive to continue with the update.
If several updates have already been performed on the system, the previously used kernel versions are still stored under /boot. As a general rule, only the most recent or the currently used kernel is required.
Automatic deletion of old kernels
If the update24/pruneoldkernel variable is set to yes prior to the update, the older kernels will automatically be deleted prior to the next update attempt. The currently running kernel and the respective latest kernel of each kernel version (2.6.18/2.6.26/2.6.32) are preserved.
Attention: It is not necessary to set the variable on OXASE systems (Single Server). /boot is automatically cleaned during the update.
Manual deletion of old kernels
If the message continues to appear, a manual check must be performed to see if sufficient space can be created on the hard drive by deleting unnecessary kernels. We have provided a script for this purpose, which provides support during the deletion of outdated kernels. It can be installed and run as follows:
Log on to the target system as root:
ssh root@targetsystem
Download the program:
chmod +x /tmp/univention-prune-old-kernel
Run the program:
/tmp/univention-prune-old-kernel
The program now displays the package of the currently running kernel and then asks for all other kernel packages installed in the system whether they should be deleted. This can be answered by pressing y to delete the kernel package or n to keep the kernel package.
root@targetsystem:~# /tmp/univention-prune-old-kernel
Package name of currently running kernel: linux-image-2.6.26-ucs36-amd64
Checking for old kernel packages…
Remove linux-image-2.6.18-ucs155-amd64? [yN] y
Removing kernel package linux-image-2.6.18-ucs155-amd64 … done.
Remove linux-image-2.6.18-ucs155-xen-amd64? [yN] ndone.
root@targetsystem:~#