Since yesterday, each time I try to connect to an ssh server, I got asked for my password. What should I do to make SSH not ask for my password each time.
Check directory permissions, and file permissions.
$HOME can't be writeable by group or other.
$HOME/.ssh needs to have
700 permissions, not readable, writeable or executable by group and other.
$HOME/.ssh/authorized_keys to be not writeable or executable by anyone.
If you find that permissions aren't strict enough, try to figure out what caused the problem. Last time this happened to me, I had compiled PHP from scratch. Executing
make install as root (Slackware) changed the permissions and ownership of
/home as I recall, and kept ssh from working with
id_rsa.pub files that had been in place and working for ages. You want to determine what caused the problem, as changed directory ownership and/or permission can happen because of a rootkit install or something like that.