It sounds like you don't have the GD extension installed. I don't use Ubuntu any longer, but I think it may be named php5-gd,...
I've observed that running a filesystem check (fsck) on the disk doesn't permanently resolve issues, as they tend to recur within a few days. Interestingly,...
Command line interface for testing internet bandwidth using speedtest.net How to check Internet Speed via Terminal?
How I converted a VMware VM to KVM
There's lots of info on the net on achieving that, but I found it a bit too scattered, and had to combine instructions from...
ls-command: how to display the file size? ls -lah -l use a long listing format -a, --all do not hide entries starting with. -h --human-readable When used with the -l...