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

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

[BrookHarty]

Everyone I know switched to SSH and dumped RSH. Keyfiles are your friend.

ssh/scp
snoop
cat (Sometimes easier to paste a file than scp one)
tail (-100f, I dont care if you are changing the command!)
ksh (solaris standard)
du (I always catalog an entire system, quicker than find, and im impatient)
But grep, perl and less, vi are always on the list.
and bzip/gzip for log files.
telnet for testing ports.
Cron is more server process, I wouldnt coun't it as a command.

But for home use, wget, screen, links, du. Wget under screen for files.

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.

Re:Telnet ...?

[JanneM]

The main benefit of sudo is when you have many admins working on a machine. If you're not in such an environment, you really don't need sudo.

In Ubuntu the root account is not active by default, meaning you _always_ use sudo to do administrative tasks. And after geting used to that I feel distinctly uncomfortable with actually having a root shell open and unprotected on the Redhat box. If nothing else I know myself and know it's only a matter of time until I type something into the wrong terminal (and I know that from previous experience)...

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.

GNU Screen.

[SlapAyoda]

I'm surprised at how few serious *NIX Administrators I know are using GNU Screen. For some reason, it seems that the majority of them have not yet discovered the sheer power of the console window manager. It allows me to manage dozens of virtual windows all within the same terminal. In addition to eliminating the need to window-switching on my local machine, it also allows me to perform complex select, copy, and paste operations using only my keyboard. WIthout using a mouse, I can select and copy text in one window, advance into another window, and paste the text. The best part is that if my DSL drops or I decide to reboot my computer, all of my screened sessions stay on the server, leaving my work in exactly the same place as it always was, and with a nice scrollback history. I couldn't work without it.

Tsync

[Earlybird]

You may want to check out Tsync, one of the recent Google "Summer of Code" winners: "Tsync is a user-level daemon that provides transparent synchronization amongst a set of computers. Tsync uses a peer-to-peer architecture for scalability, efficiency, and robustness." Unlike rsync, Unison, etc., Tsync is a locally installed daemon which automatically and transparently syncs two or more hosts.

My list...

[ledow]

- ssh (file transfers, port forwarding, encryption and remote login in one tiny tool. I even use it in place of WEP or WPA)
- pico (can't stand vi but pico is small and has enough of a help that I don't have to memorise keystrokes)
- grep, sed (with grep and sed, you can pretty much manipulate any file/program output into whatever you want, strip IP's out of errors/logs, etc.)
- x11vnc (like any other VNC program but supports Tight encoding and also lets me see what an EXISTING X session is doing. Combined with a script that seds/greps the auth code from the process list and you have automated remote desktop)
- screen (if for no other reason than it lets you start a job at work (like a kernel compile) and watch it's progress throughout the day even if you have to log off in between. And when you get home, you can still check on it)
- tinyproxy (wonderful small, easy to use web-proxy that I tunnel into from work to bypass the far-too-restrictive filters in the schools that I work in)
- slocate (worth it's weight in gold when you have it auto-indexing overnight across all filesystems. Where's that file I used ten years ago that had Xen in the name? a simple command, 2 seconds wait and you get the full path).
- dnsmasq (tiny util, bung it a massive list of public DNS servers and point your DNS requests to 127.0.0.1 and it will loop through them all until it gets a response. Failover to other servers, built-in full DHCP server, invaluable behind a NAT, simple config. Saved my life I-don't-know-how-many-times when my ISP DNS servers were feeling flaky. No one even noticed that half the time our ISP's weren't responding to DNS at all.)
- lsusb, lspci, /proc/cpuinfo, free etc. (Invaluable for hardware discovery. Boot a knoppix CD, run those commands and instantly you know everything about the hardware that you need to know.)
- dd, cat, more, sh, etc.(where would we be without them?)