Ssh keys on floating ip address

hello, i have two AIX6.1 machines. one of them is the "live" server that the users are connected to in order to do their job and the second is acting as a backup server just in case that there is some problem with the "live" one. i noticed that when i de-activate the resources from the one server and activate them on the backup server i have a problem with ssh keys because i have to remove the entry of the server from known_hosts file and authenticate the connection again. in known_hosts file i have the keys for the physical name of the 2 servers (ex. server1, server2) and also the key for the floating ip address (ex. server_float). when i switch applications from one server to another i have to remove the entry for server_float and re-authenticate the connection so that a new entry will be added. is there a way to have an entry or 2 in my known_hosts file that will accept connections from either server (server1, server2) without needing to remove the entry and add it again? Thank you

Host keys are typically defined in /etc/ssh.

You could use the same host keys on both systems or define a third for "server_float" that is common to the two systems - if "server_float" has a separate IP address and is not an alias.

ok i will try the first option to have the same public keys on /etc/ssh. Thank you

i cannot make it work. i tried the first option but i think i can never make it work like that because as soon as server_float is down then i need to re-authenticate the keys on the last active server. so i tried to the second suggestion, to define a separate key for server_float but i dont seem to make it correctly. this is the steps that i followed so correct me if i missed anything: 1. from the server that server_float is active i copied the keys ssh_host_rsa_key ssh_host_rsa_key.pub and i give them a separate name 2. i added the new key ssh_host_rsa_CLUSTER_key on sshd_config file and restart sshd services 3. server_float is made inactive from server1. i send the new keys ssh_host_rsa_CLUSTER_key ssh_host_rsa_CLUSTER_key.pub on server2 under /etc/ssh 4. i added the key ssh_host_rsa_CLUSTER_key on sshd_config file on server2 and restarted the sshd services. 5. i activate server_float on server2 however, when i try to connect to server_float when it is active on server2 i get prompted to re-authenticate the connection. did i miss anything?