Adding public key to ~/.ssh/authorized_keys does n

Question

I added the public ssh key to the authorized_keys file. ssh localhost should log me in without asking for the password.

I did that and tried typing ssh localhost, but it still asks me to type in the password. Is there any other setting that I have to go through to make it work?

I have followed instruction for changing permissions:

Below is the result if I do ssh -v localhost

debug1: Reading configuration data /home/john/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to localhost [127.0.0.1] port 22.
debug1: Connection established.
debug1: identity file /home/john/.ssh/identity type 1
debug1: identity file /home/john/.ssh/id_rsa type -1
debug1: identity file /home/john/.ssh/id_dsa type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.7p1 Debian-8ubuntu3
debug1: match: OpenSSH_4.7p1 Debian-8ubuntu3 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.7p1 Debian-8ubuntu3
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-cbc hmac-md5 none
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Host 'localhost' is known and matches the RSA host key.
debug1: Found key in /home/john/.ssh/known_hosts:12
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Offering public key: /home/john/.ssh/identity
debug1: Server accepts key: pkalg ssh-rsa blen 149
debug1: PEM_read_PrivateKey failed
debug1: read PEM private key done: type <unknown>

Then it asks for passphase after the above log. Why isn't it logging me in without a password?

Answer 1

user is your username

mkdir -p /home/user/.ssh
ssh-keygen -t rsa
touch /home/user/.ssh/authorized_keys
touch /home/user/.ssh/known_hosts
chown -R user:user /home/user/.ssh
chmod 700 /home/user/.ssh
chmod 600 /home/user/.ssh/id*
chmod 644 /home/user/.ssh/id*.pub
chmod 644 /home/user/.ssh/authorized_keys
chmod 644 /home/user/.ssh/known_hosts

Answer 2

the desperate may also make sure they don't have extra newlines in the authorized_keys file due to copying id_rsa.pub text out of a confused terminal.

Answer 3

Write command:

chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys

After you do this, make sure your dir is like that:

drwx------ 2 lab lab 4.0K Mar 13 08:33 .
drwx------ 8 lab lab 4.0K Mar 13 08:07 ..
-rw------- 1 lab lab  436 Mar 13 08:33 authorized_keys
-rw------- 1 lab lab 1.7K Mar 13 07:35 id_rsa
-rw-r--r-- 1 lab lab  413 Mar 13 07:35 id_rsa.pub

Answer 4

Another issue you have to take care. If your generated file is not default id_rsa and id_rsa.pub

You have to create .ssh/config file and define manually which id file you are going to use with the connection.

Example is here:

host remote_host_name
hostname 172.xx.xx.xx
user my_user
IdentityFile /home/my_user/.ssh/my_user_custom.pub

Answer 5

Also be sure your home directory is not writeable by others

chmod g-w,o-w /home/USERNAME

Answer is stolen from here

Answer 6

Make sure that the target user has a password set. Run passwd username to set one. This was required for me even if password SSH login was disabled.