Re: [tlug] Ubuntu 16.04-LTS SSH authentication problems

[Curt Sampson <cjs@example.com>]

When you have issues with SSH authentication, the first step is always
to look at /var/log/auth.log or equivalant.

Second, of course, is to check permissions on the user's $HOME,
$HOME/.ssh and the files underneath those directories. Ownership mustn't
be weird (though they don't all have to be owned by the user, $HOME
can be owned by root, though not $HOME/.ssh IIRC) but permissions are
particularly important; also IIRC having $HOME/.ssh/authorized_keys
group writable, even if it's by the user's group and he's the only one
in it, will result in an authentication failure.

The next step is to use the `-v` option when you SSH in and have a look
at what it's asking you for in terms of authentication.

Oh, and please, please set `PasswordAuthentication no` in your
/etc/ssh/sshd_config. Allowing password authentication has to be pretty
near the number one way Linux systems get cracked.

cjs
-- 
Curt Sampson         <cjs@example.com>         +81 90 7737 2974

To iterate is human, to recurse divine.
    - L Peter Deutsch