If using Corosync/Pacemaker and you get a "ghost" node (due to changing the hostname of a node, for example), the command to delete the node is:

cibadmin --delete --obj_type nodes --crm_xml '<node id="hostname" />'
hostname should be replaced with the name of the node.

You absolutely do want to remove these ghost nodes, as they can prevent elections/allocation of resources, especially if using a two-node cluster.

If using File History for your backups on Windows, do not copy files directly from the backup folders/disk. It appears (but I haven't tracked down exactly what) that there is some permissions applied to the files that doesn't show in the standard File Permissions UI.

When compiling x32 libraries on an x64 (Ubuntu) platform, you need to have gcc-multilib and/or g++-multilib installed. Otherwise linking will fail with "library not found" messages.

NFS mounts have the bg option, allowing background mounting. This means that if the initial mount times out (for example depending on a network interface that isn't configured yet), it will spawn a background process that retries the mount periodically, and return as if it had succeeded.

Through the use of a plugin for TotalCommander it is possible to browse and extract from all the formats supported by 7zip.
If you use a 32bit build of FreeCommander (the free version is 32bit) you will need the 32bit installation of 7zip as well.