Slashdot Mirror
Top 10 Items in the Linux Admin Toolkit
Joe Barr writes "Joe 'Zonker' Brockmeier has listed his favorite top ten tools for Linux system administration in a story on Linux.com, one of Slashdot's sister sites." From the site: " Since I spend a lot of my time working with text files, either when I'm writing and editing or when I'm mucking with configuration files and shell scripts, I've become very attached to my editor of choice -- Vim. Over the years, I've tried a lot of other editors, but none of them has been sufficient to coax me away from Vim. Part of the reason for that is the fact that I no longer have to think about using Vi-style keybindings, and adjusting to anything else would seriously hinder my productivity."
Shame on those that only provide info, text, or worst, html documentation (or none)
For reading HTML docs over ssh or on an X11-less machine, might I recommend w3m? It's a very comfortable text-mode web browser. Unlike Lynx, it renders tables nicely, and even makes a brave attempt at frames.
-Stephen
I'm actually suprised this guy used telnet. I find netcat (man nc) as a much better alternative. I can script it, I can do udp, and I can do port "testing".
While rsync is very nice for syncing files, I've found another, somewhat related tool much nicer for my purposes. I have a desktop and a laptop computer, and to a great extent I work on the same files on both. Syncing my home directories could be done using rsync to some degree, but it's rather painful if you have modified files on both sides.
This is where unison comes in handy. It keeps two directories synchronized nicely, adjusting changes in both directions automatically and querying the user in case of collisions. One of my favorite tools, and I'm sure I'm far from being the only one with a need for something like it.
Now, some of those are "well-known", but there are plenty there that few people (even on Slashdot) are likely to be overly familiar with.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
ethtool and mii-tool. The Cisco 2970 switch we use has the knack of initializing the interface in half-duplex mode if the port is set to "Auto". Easily fixed by setting the port to Full, but useful nonetheless.
/etc/hosts.allow and /etc/hosts.deny, or where pop3/imap are looking for PEM certificates to configure pop3s/imaps, etc...
/proc filesystem. Favorites include /proc/net/dev, and /proc/uptime, /proc/cpuinfo, /proc/loadavg. Good for aggregating individual server load data in a cluster.
... permissive. Cut down on access to your logfiles and to config files in /etc.
.. might take a while. When you forgot to & your command, use CTRL+Z then bg your job.
strings. Good to check if executables are using
vmstat. Think your system is paging, or a card is generating too many interrupts?
awk and sed. Mentioned elsewhere, but priceless.
chmod. I think the Linux filesystem permissions are too
*quota*. A must for restricting disk space use.
umask. When you need root, set your default umask fairly tight. I use 0077, but when you need to cpan some common perl modules, switch to the more common 0022.
jobs, fg and bg. Old-school unix commands to play with jobs that
There may be more, but I can't think of any others right now...
Screen is very useful. I think of it as providing virtual terminals (you know, Ctrl-F1 to Ctrl-F6) but over remote login (usually ssh in my case)
My normal usage is like so:
ssh into the box
screen -r (resume session, that was created first time I went in after bootup, with screen -S)
Ctrl-A Ctrl-N (next virtual terminal) to flick through things i have running, usually centericq (text multi protocol chat client) and btdownloadcurses, or the results of a compile I left going.
Ctrl-A Ctrl-C (open new virtual terminal) which gives you another command prompt. Here I'll wget a tarball, extract it, start the compile, then Ctrl-A Ctrl-N back to centericq
I'll disconnect from the box (Ctrl-A Ctrl-D to disconnect from screen, then Ctrl-D to close the login shell), go home, reconnect from one of my other machines, go through the same process.
Also, I can stay connected, go to another machine, and use screen -x to have multiple connections to the same screen. In the case of a dropped connection, and screen thinks my old login is still valid, screen -rD will disconnect the old login.
Oh, and Ctrl-A ? will show all the in-screen escape sequences. Some of them I haven't used (there is one to do horiz split display, but it crashes btdownloadcurses), but look like they could be even more useful!
But really, the best part is not having programs killed on me because the internet connection dropped (as happens all too often around these parts).
I was actually going to say something very similar, and then I realized that I use telnet over netcat for certain purposes, because telnet notifies me when it actually connects. However, a couple minutes ago I realized I was being an idiot, because 'nc -v' does the same thing.
Also, if you haven't already, check out nmap-ncat.
Better to light a candle than to curse the darkness.