I used the command "ssh-keygen -t rsa" to create a key so that 2 of my servers know each other so i can cron a rsync job, but when I try to transfer the key "ssh-copy-id -i ~/.ssh/id_rsa.pub firstname.lastname@example.org" I get "-bash: ssh-copy-id: command not found", what am I missing?
Not sure what ssh-copy-id does but you should be able to do it manually.
Then you might need to change permissions on authorized_keys so that no-one else can write it.
scp ~/.ssh/id_rsa.pub email@example.com:./
cat id_rsa.pub >> /home/user/.ssh/authorized_keys