1. Making a Temporary Filesystem (Ramdisk)
are several reasons to make a temporary RAM-based filesystem such as
fast read/write times or to guarantee that the files will not persist
after reboot. Making such a “fake” filesystem is easy, and just
requires one command.
mount -t tmpfs tmpfs /mytemppartition -o size=1024m
is the location you wish to mount (it must already exist) and 1024m
is the desired size of the ramdisk.
2. Quickly Scheduling Commands
Linux pros almost certainly know the at
command, it lets you set a specific time for a job to be run. You simply say what to do and when to do it, and at
takes care of the rest. Its usage can be confusing for some, so here’s one common way of scheduling a task with at
at 12:30 #Enter key
If you want to verify that it worked, you can easily list the sceduled jobs with
3. Re-run Previous Commands
Perhaps you ran a long complicated command, but forgot to preface it with sudo
or maybe you didn’t add some necessary options to the end. Instead of
retyping the whole thing or going back through your shell history, you
can use “double bangs” to represent your last command.
you’re the type who tracks your command history numbers, you can use
the same approach to recall any previous command by referencing its
4. Find the PID of a Process
you need to kill a particular process but don’t have its PID, there’s a
simple shortcut to find it – the pgrep command. It doesn’t do anything
that can’t be done with a combination of ps
, but every little bit helps.
5. Show Listening Ports and their Processes
you need to see what’s listening for connections on your system, and
the processes handling those connections, the old trusty netstat tool is
up to the job. Try
to see just such a list.
6. SSH Without Passwords
people, such as this author, use SSH on a nearly constant basis. It’s a
great tool, there’s no denying that, but having to constantly retype
your passwords can get annoying. Instead, you can simply copy your
(public) SSH information to the remote machine, allowing it to
authenticate you without requiring your password, and all you need is a