adding ssh public key to server - ssh

Question

I'm trying to push my id_rsa.pub to server so I can ssh into it.
I've run the following command,
cat ~/.ssh/id_rsa.pub | ssh -v -p 12345 myname#123.45.67.8 'cat >> ~/.ssh/authorized_keys'
which returns the following debugging:
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug1: Connecting to 123.45.67.8 [123.45.67.8] port 12345.
debug1: Connection established.
debug1: identity file /Users/myname/.ssh/id_rsa type 1
debug1: identity file /Users/myname/.ssh/id_rsa-cert type -1
debug1: identity file /Users/myname/.ssh/id_dsa type -1
debug1: identity file /Users/myname/.ssh/id_dsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9p1 Debian-5ubuntu1.4
debug1: match: OpenSSH_5.9p1 Debian-5ubuntu1.4 pat OpenSSH_5*
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr 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: Server host key: RSA [some server host key]
debug1: Host '[123.45.67.8]:12345' is known and matches the RSA host key.
debug1: Found key in /Users/myname/.ssh/known_hosts:6
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /Users/myname/.ssh/github_rsa
debug1: Authentications that can continue: publickey
debug1: Offering RSA public key: /Users/myname/.ssh/id_rsa
debug1: Authentications that can continue: publickey
debug1: Trying private key: /Users/myname/.ssh/id_dsa
debug1: No more authentication methods to try.
Permission denied (publickey).
I can't figure out what the problem is..
can anybody please help me out?

Answer 1

Key based authentication will only work if the authorized_keys has
Correct permissions.
Try to do a chmod 600 ~/.ssh/authorized_keys

Answer 2

Your command will only work if you can ssh to the server by entering a password. It also requires the dir ~/.ssh to be created on the remote server and lastly (as Jan-Erik Revsbech points out) the permissions on the local and the remote ~/.ssh needs to disallow others reading it.
If you instead use ssh-copy-id remote-server to copy your keys, then both the dir and permissions on the remote system will be set correctly. It will still require you to enter the password the first time, though.

Answer 3

Make sure to also set the correct owner :)
I tried ssh-copy-id remote-server as suggested by Ole and got an error like this:
Cannot write to .ssh/authorized_keys. Permission denied
The directory ~/.ssh as well as the file authorized_keys were already present on the server and set up with the right permission... but for the wrong user! Here is, what solved it:
chown right-user:right-user .ssh
chown right-user:right-user .ssh/authorized_keys
I changed the owner of the file and the directory. Then ssh-copy-id worked.