Not enough space on /boot

After trying to update on two of my servers both gave me the following error.

[code]**** Starting univention-updater with parameter=[’/usr/share/univention-updater/univention-updater’, ‘net’, ‘–updateto’, ‘4.0-5’, ‘–ignoressh’, ‘–ignoreterm’]
starting net mode
—>DBG:update_available(mode=net, cdrom_mount_point=/cdrom, iso=None)
Checking network repository
Update to = 4.0-5
**** Downloading scripts at Tue Aug 9 16:24:16 2016
**** Starting actual update at Tue Aug 9 16:25:46 2016
Running script
Tue Aug 9 16:25:46 EST 2016

Please check the release notes carefully BEFORE updating to UCS 4.0-5:
English version:
German version:

Please also consider documents of following release updates and
3rd party components.

Do you want to continue [Y/n]?
Custom preupdate script /var/lib/ not found
Checking for space on /var/cache/apt/archives: OK
Checking for space on /boot: failed
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
config registry variable update40/checkfilesystems to “no”.
But be aware that this is not recommended!
Old kernel versions on /boot can be pruned automatically during
next update attempt by setting config registry variable
update40/pruneoldkernel to “yes”.

Error: Update aborted by pre-update script of release 4.0-5


      Please any instructions on how to overcome this problem without skipping  UCS check ? 

thank you,

Rolando Riley

ucr set update40/pruneoldkernel=yes

i used above command but still it cannot continue

The issue here is the space on /boot -> the ucr set update40/pruneoldkernel=yes variable should automatically clean up old kernels, but if the /boot is very small or if there is other stuff, that may be not enough. You need to free up diskspace on /boot to continue.

I’ve used the suggestions in this stack to remove old kernels.