Sort installed RPMs by size

Keep forgetting this one, to list all RPM packages installed on a Linux (Red Hat / CentOS) machine sorted from the largest to the smallest in size:

rpm -qa --queryformat '%{size} %{name}\n' | sort -rn | more

This outputs something like this:

[root@healthy ~]# rpm -qa --queryformat '%{size} %{name}\n' | sort -rn | more
87389896 kernel
66720559 glibc-common
35274936 perl
30873913 valgrind
28767659 selinux-policy-targeted
27805586 redhat-logos
27022854 valgrind
26982540 mesa-libGL
24517704 mesa-libGL
22091978 python
20474820 specspo

How to mount an LVM partition

This details the commands I had to run to mount a CentOS 5.1 main disk into another machine. Because of LVM using mount on standard scsi partitions is not enough.

Assuming main physical disk: /dev/sda
Second physical disk: /dev/sdb

1. Run pvscan to list the physical volumes found in any block device of the system. Among error lines this returned PV lines for /dev/sda2 and /dev/sdb2. On the same line was the name of the volume group, in my case 'sysvg'
2. Made the 'sysvg' volume group active by typing lvchange -ay sysvg. This created a new entry in the /dev/sysvg
3. Doing an ls /dev/sysvg showed the different volumes under that volume group, from there simply had to do: mount /dev/sysvg/root.vol /mnt
4. When done: umount /mnt && lvchange -an sysvg