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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands tagged host from sorted by
Terminal - Commands tagged host - 15 results
sed -i 's/oldname/newname/' /etc/hosts /etc/hostname
2014-11-02 22:03:48
User: adria
Functions: sed
Tags: sed hostname host

With sed you can replace strings on the fly.

getent hosts <host>
dig +short -x
10,30,50 * * * * ping -c1 -w3 >/dev/null
2012-02-06 14:54:15
User: bashrc
Functions: ping

Cleaner with a mailto assignment in crontab (if the command fails you get an email):

[email protected]

10,30,50 * * * * ping -q -c1 -w3 >/dev/null

10,30,50 * * * * ping -q -c1 -w3 | grep '1 received' - || mail -ne -s'Host not reachable' [email protected]
2012-02-06 10:42:46
User: knoppix5
Functions: grep mail ping

Every 20 minutes test if host with IP is 'dead' or not reachable.

The line should be put in your crontab file.

10,30,50 * * * * ping -q -c1 -w3 | grep '1 received' - || env DISPLAY=:0 xeyes
2012-02-06 09:40:11
User: knoppix5
Functions: env grep ping
Tags: ping host crontab

Every 20 minutes ping host with IP address If it's not 'alive' or not reachable, then display something eye-catching (here xeyes) on the desktop.

Hint for newbies: edit crontab with

crontab -e
while true; do date; ssh <YOUR HOST HERE> "echo" && echo "HOST UP" && break; sleep 60; done
getent hosts google.com | awk '{print $1}'
2010-11-03 12:02:05
User: depesz
Functions: awk getent

has the benefit of being a bit more cross-platform.

host google.com|awk '{print $NF}'
dig hostname a +short
gethostip -d hostname
host foo.com|grep " has address "|cut -d" " -f4
2010-10-29 17:01:37
User: dinomite
Functions: cut grep host

Get just the IP address for a given hostname. For best results, make this a function in your shell rc file so that it can be used for things like traceroute:

Titus:~$ traceroute `getip foo.com`

traceroute to (, 64 hops max, 52 byte packets

while read n; do host $n; done < list
dig -x
2009-09-28 15:13:34
User: postrational
Functions: dig

Performs a reverse DNS lookup, variants include:



for i in `cat names.txt`; do host -r $i [nameserver]; done
2009-08-22 09:26:31
User: hemanth
Functions: host
Tags: host

DNS cache snooping