HPR1167: Kernels in the Boot, or What to Do When Your /boot folder Fills Up

Summary: Synopsis of the Problem You may hae heard me mention that I purchased a used rack server a couple years ago to help teach myself Linux server administration.  It's an HP DL-380 G3 with dual single core Zeons and 12Gb of RAM.  It came with two 75Gb SCSI drives in RAID1, dedicated to the OS.  Since the seller wanted more for additional internal SCSI drives, and those old server drives are limited to 120Gb anyway, I plugged in a PCI-X SATA adapter and connected  750Gb drive externally and mounted it as /home.  I moved over the 2Gb USB drive I had on my Chumby (as opposed to transferring the files) and it shows up as /media/usb0.  I installed Ubuntu server 10.04 (recently updated to 12.04) because CentOS didn't support the RAID controller out of the box and I had frustrated the lack of support for up to date packages on Debian Lenny on the desktop. With 75Gb dedicated to the OS and application packages, you can imaging my surprise when after a update and upgrade, I had a report that my /boot was full.  It was until I look at the output from fdisk that I remembered the Ubuntu installer created a separate partition for /boot.  At the risk of oversimplifying the purpose of /boot, it is where your current and past kernel files are stored.  Unless the system removes older kernels (most desktop systems seem to) the storage required for /boot will increase with every kernel upgrade. This is the output of df before culling the kernels Filesystem              1K-blocks      Used  Available Use% Mounted on /dev/mapper/oriac-root   66860688   6593460   56870828  11% /udev                               6072216           4    6072212   1% /dev tmpfs                              2432376       516    2431860   1% /run none                               5120                 0       5120       0% /run/lock none                              6080936            0    6080936    0% /run/shm cgroup                           6080936            0    6080936   0% /sys/fs/cgroup /dev/cciss/c0d0p1          233191    224953          0         100% /boot /dev/sda1                       721075720 297668900  386778220  44% /home /dev/sdb1                     1921902868 429219096 1395056772  24% /media/usb0 This directory listing shows I had many old kernels in /boot abi-2.6.32-24-generic-pae abi-2.6.32-35-generic-pae abi-2.6.32-36-generic-pae abi-2.6.32-37-generic-pae abi-2.6.32-38-generic-pae abi-2.6.32-39-generic-pae abi-2.6.32-40-generic-pae abi-2.6.32-41-generic-pae abi-2.6.32-42-generic-pae abi-3.2.0-29-generic-pae abi-3.2.0-30-generic-pae abi-3.2.0-31-generic-pae abi-3.2.0-32-generic-pae config-2.6.32-24-generic-pae config-2.6.32-35-generic-pae config-2.6.32-36-generic-pae config-2.6.32-37-generic-pae config-2.6.32-38-generic-pae config-2.6.32-39-generic-pae config-2.6.32-40-generic-pae config-2.6.32-41-generic-pae config-2.6.32-42-generic-pae config-3.2.0-29-generic-pae config-3.2.0-30-generic-pae config-3.2.0-31-generic-pae config-3.2.0-32-generic-pae grub initrd.img-2.6.32-24-generic-pae initrd.img-2.6.32-35-generic-pae initrd.img-2.6.32-36-generic-pae initrd.img-2.6.32-37-generic-pae initrd.img-2.6.32-38-generic-pae initrd.img-2.6.32-39-generic-pae initrd.img-2.6.32-40-generic-pae initrd.img-2.6.32-41-generic-pae initrd.img-2.6.32-42-generic-pae initrd.img-3.2.0-29-generic-pae initrd.img