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."

Comments

Most important item

[Anonymous Coward]

Condoms! With all the groupies chasing Linux system admins, you can never have too many condoms!

Re:Vim? Emacs foreva!

[MORTAR_COMBAT!]

the article said "toolkit" not "tool shed, tool warehouse, and tool factory on wheels".

FLAME ON! Or not....

[Bonker]

Yes, let's dig one of the oldest flamewars back up in the summary rather than discuss some of the article's other excellent information.

TFA mentions WGet, one of the most wonderful, most needed applications that most users and admins ON EVERY PLATFORM don't know they need. Why not focus on this rather than ressurect the text editor wars?

Re:FLAME ON! Or not....

[Bogtha]

Why not focus on this rather than ressurect the text editor wars?

Big flamewar == more pageviews. More pageviews = more ad impressions. More ad impressions == higher profits.

Slashdot editors post "provoking" (i.e. flamebait/troll) summaries/articles so frequently that you can essentially rule out stupidity and go straight to malice.

Re:Vim? Emacs foreva!

[Anonymous Coward]

The only 3 commands any Emacs user needs to know:

Ctrl-x
Ctrl-c
vi

Mine

[hackstraw]

In alphabetical order:

• [rs]sh - enables me to go places w/o passwords, copy files, and remotely execute commands. I can't live without it
  
• cron - does my work for me while I sleep, and mails me the results in the morning
  
• grep - the filter of filters. Keeps down the signal to noise ratio
  
• less - the pager of pagers. With a proper lessopen/pipe, you can do what no man has done before. You can go backwards in files, although I guess some 'more's can do this now. Less always can. It also highlights text searches so I don't have to search for what I just searched for.
  
• man - that's where they hide the documentation. Shame on those that only provide info, text, or worst, html documentation (or none)
  
• perl - anything that any other command cannot do, or cannot do well enough, perl can with some coaching.
  
• rsync - although its binary diff algorithm is not very good, rsync is close to heavenly, especially
• when teamed with [rs]sh and cron
  
• telnet - no, I never telnet to login to a machine, but I do it to test if a port is open, what's listening there, etc. very handy.
  
• vim - good editor, I can live with vi, but that makes me a little grumpy. I simply do not know or care to learn emacs. Its just a text editor.
  
• zsh - excellent shell. Very user friendly, consistent error messages, powerful. It can do anything any other shell can do and more. I understan
  d that bash has made some progress over the years, but zsh is my friend.
  
• /dev/null - where I put all of my important stuff. So should you!
  
  
• Honorable mention - /bin/sh Only because it is always there by definition on UNIX systems, and a good shell programming language. tcsh, csh, and zsh are not as good as /bin/sh, and its always available, but a little boring to write about.
  

Re:Mine

[Stephen Williams]

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

Re:Mine

[mindriot]

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.

Re:Mine

[FyRE666]

egrep is more useful than grep
netcat (nc) is more better than telnet

I don't wish to be picky, but it's
"netcat (nc) is more betterer than telnet"

Please prof reed yor articals!

I got yer flamewar right here!

[adavies42]

Wget sucks, curl rules!

Telnet ...?

[stevey]

It is suprising the author chose "telnet" as one of the programs in his list.

Sure it is useful for diagnosing random problems, and troubleshooting things - for example connecting straight to a webserver, or simulating a POP3 login request, but I've always preferred netcat.

netcat is much more useful, it allows you to bind to sockets and handling incoming requests as well as make outgoing ones this introduction is a good read.

Missing tools from the list? curl, links/lynx, rsync, sudo, nmap, lsof, and less.

rm

[Skadet]

rm

preferably with the -Rf options.

Cream for Vim

[digitect]

I'll plug my own project here: Cream is Vim tricked out in single mode with all the development tools pre-configured with all useful shortcut keys self-documented in the pull-down menus. You won't need to go searching through the help ever again.

Re:SSH

[fimbulvetr]

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".

Depends on the admin role I'm in

[jd]

For network administration, I'd probably have a top 10 of:

• hping3
• bing
• pchar
• ping
• traceroute
• ncat
• tcp dump
• webmin
• wget
• ngrep

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.

Maybe a few lesser-known

[toofast]

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.

strings. Good to check if executables are using /etc/hosts.allow and /etc/hosts.deny, or where pop3/imap are looking for PEM certificates to configure pop3s/imaps, etc...

vmstat. Think your system is paging, or a card is generating too many interrupts? /proc filesystem. Favorites include /proc/net/dev, and /proc/uptime, /proc/cpuinfo, /proc/loadavg. Good for aggregating individual server load data in a cluster.

awk and sed. Mentioned elsewhere, but priceless.

chmod. I think the Linux filesystem permissions are too ... permissive. Cut down on access to your logfiles and to config files in /etc.

*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 .. might take a while. When you forgot to & your command, use CTRL+Z then bg your job.

There may be more, but I can't think of any others right now...

Re:Other comments on GNU Screen?

[Wizarth]

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).

Re:SSH

[Pheersome]

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.