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Remove invalid key from the known_hosts file for the IP address of a host

Terminal - Remove invalid key from the known_hosts file for the IP address of a host
ssh-keygen -R `host hostname | cut -d " " -f 4`
2009-09-23 14:58:28
User: flart
Functions: cut hostname ssh ssh-keygen
5
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Remove invalid key from the known_hosts file for the IP address of a host

Quick shortcut if you know the hostname and want to save yourself one step for looking up the IP address separately.

Add to favourites | Report as malicious

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
ssh-keygen -R $(dig +short host.domain.tld)
2012-01-19 15:08:50
User: atoponce
Functions: dig ssh ssh-keygen
Tags: ssh dig ssh-keygen
2
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Down
Remove invalid key from the known_hosts file for the IP address of a host

Quick shortcut if you know the hostname and want to save yourself one step for looking up the IP address separately.

Comments (1) | Add to favourites | Report as malicious
for HOSTTOREMOVE in $(dig +short host.domain.tld); do ssh-keygen -qR $HOSTTOREMOVE; done
2012-01-19 15:57:10
User: bibe
Functions: dig ssh-keygen
Tags: ssh dig ssh-keygen
0
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Remove invalid key from the known_hosts file for the IP address of a host

Works for multiple hosts (such as www.google.com) and/or wrong hosts.

Show sample output | Comments (2) | Add to favourites | Report as malicious

Know a better way?

If you can do better, submit your command here.

What others think

nice! because I always delete the wrong line in the known_hosts file upon key errors, ever since the hostnames started being hashed by default. This is great, although I wonder if this will get each and every instance since the hosts' key may be listed under three different names: (1) the bare hostname, such as "bob", (2) the FQDN, such as "bob.example.com", or (3) the IP address. I'm guessing ssh-keygen just deletes entries corresponding to exactly what the input was.

Comment by bwoodacre 399 weeks and 6 days ago

@bwoodacre

Exactly. You need to run 'ssh-keygen -R' for every instance of the host in the known_hosts file.

It's nevertheless more comfortable than editing it by hand IMO :-)

Comment by flart 399 weeks and 5 days ago

Repeat after me: avoid backticks, they're evil ...

Comment by assarbad 273 weeks and 6 days ago

Your point of view

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