Commands by ztank1013 (9)

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Get ethX mac addresses
I much prefer using /sbin/ip over /sbin/ifconfig for most everything. I find the interface and output to be much more consistent and it has many abilities that ifconfig, route, etc. do not. To get the mac address for only one interface, add 'show dev [interface]' to the 'ip link' part of the command: ip link show dev eth0 | grep 'link/ether' | awk '{print $2}' . Also, both this command and the ifconfig one do not require root access to run, so the sudo is not necessary.

View the newest xkcd comic.

Create a DOS floppy image
mount with: mount -t msdos -o loop ./floppy.img /tmp/mnt

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Watch several log files in a single window
It works like a "tail -f" on several files. Use the number keys 0-9 to set a baseline in the numbered window. Pressing "b" let you scroll back in one of the windows.

Convert flv without re-encoding

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Quickly generate an MD5 hash for a text string using OpenSSL
Thanks to OpenSSL, you can quickly and easily generate MD5 hashes for your passwords. Alternative (thanks to linuxrawkstar and atoponce): $ echo -n 'text to be encrypted' | md5sum - Note that the above method does not utlise OpenSSL.

grep apache access.log and list IP's by hits and date - sorted

Remove grep itself from ps
When you 'ps|grep' for a given process, it turns out that grep itself appears as a valid line since it contains the RE/name you are looking for. To avoid grep from showing itself, simply insert some wildcard into process' name.


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: