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Remove a line in a text file. Useful to fix "ssh host key change" warnings

Terminal - Remove a line in a text file. Useful to fix "ssh host key change" warnings
sed -i 8d ~/.ssh/known_hosts
2010-07-10 14:22:34
User: prayer
Functions: sed
29
Remove a line in a text file. Useful to fix "ssh host key change" warnings

Alternatives

There are 9 alternatives - vote for the best!

Terminal - Alternatives
ssh-keygen -R <the_offending_host>
2010-07-11 19:37:24
User: bunam
Functions: ssh ssh-keygen
Tags: sed
41

In this case it's better do to use the dedicated tool

sed -i 3d ~/.ssh/known_hosts
2011-05-26 11:34:03
User: evandrix
Functions: sed
7

deletes line 3 in known_hosts text file

> ~/.ssh/known_hosts
2010-08-04 06:54:18
User: cde1985
-4

This is the quick and dirty alternative ;)

The whole file will be emptied, this is equal to /dev/null > ~/.ssh/known_hosts

echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
2010-07-11 23:09:11
User: DaveQB
Functions: echo egrep exit printf sed
Tags: sed
-13

I have this as a file called deletekey in my ~/bin.

Makes life a little easier.

Know a better way?

If you can do better, submit your command here.

What others think

On a small file it doesn't matter, but on a large file this can be quicker:

sed -i '9q;8d' filename
Comment by dennisw 268 weeks and 1 day ago

Your point of view

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