On my desktop I run a number of distros. I often ssh into the machine. However depending on which distro I am using, the RSA key is different.

So what I will do is delete ~/.ssh/known_hosts on the machine I am using and ssh in.

what i was wondering is whether using ssh-keygen and creating the same passphrase for the distros would remove this problem?

you're free to copy the keys between machines / distros as much as you want. no need to recreate them

So far as ssh is concerned, different distros = completely different computers, even if they are physically the same.

ssh is very security-conscious and when properly set up will not connect if it thinks anything could possibly be wrong (this is absolutely the correct behaviour, otherwise, why are you using the secure shell ?)

So you will have to set up the keys on the machine you ssh from, then copy them over to each different distro on your desktop, that you would like to ssh to, one at a time.

Looks like you are going to be doing a lot of rebooting between distros

Just to further clarify here: you're referring to the host key for sshd.

Better options:

1. Give each distro its own IP / hostname; or
2. copy the host keys in /etc/ssh (ssh_host_dsa_key*, ssh_host_rsa_key*) from one distro to all the others.

Nope.

Thanks guys. I went with anomie's option 2.