I have searched the list, and don't see this covered or didn't search for the right words. I'm running CentOS 4.8 and have some DVD's for 5.4. I have a lot of customized and additional software installed and would like to avoid starting over with a scratch install. After the upgrade from the DVD I would do a yum upgrade to 5.5. Is this a workable (and safe) thing to do? What should I look out for? I plan to build a clone of the boot disk in case there is a problem so I can swap it back in to the hba1 position (as soon as I find a way to make a clone of a disk with LVM ). Here is some info on the system: [root at hat /]# cat /etc/redhat-release CentOS release 4.8 (Final) [root at hat /]# uname -a Linux hat.rbt.net 2.6.9-89.0.25.ELsmp #1 SMP Thu May 6 12:28:03 EDT 2010 i686 athlon i386 GNU/Linux[root at hat .spamassassin]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/VG00-LV00 2.0G 695M 1.2G 37% / /dev/hda1 494M 25M 444M 6% /boot none 1013M 0 1013M 0% /dev/shm /dev/mapper/VG00-LV04 9.9G 5.4G 4.0G 58% /home /dev/mapper/VG00-LV05 1008M 34M 924M 4% /opt /dev/mapper/VG00-LV03 4.0G 41M 3.7G 2% /tmp /dev/mapper/VG00-LV01 7.9G 4.2G 3.4G 56% /usr /dev/mapper/VG00-LV02 4.0G 929M 2.9G 25% /var Thanks in advance for any help with this.... Bob