Passwordless SSH connection still asks for a password [duplicate]

Reading manual pages should help you:

 -Q cipher | cipher-auth | mac | kex | key | protocol-version

Queries ssh for the algorithms supported for the specified version 2. The available features are: cipher (supported symmetric ciphers), cipher-auth (supported symmetric ciphers that support authenticated encryption), mac (supported message integrity codes), kex (key exchange algorithms), key (key types) and protocol-version (supported SSH protocol versions).

Calling ssh -Q key gives you what you want:

ssh -Q key
ssh-ed25519
[email protected]
ssh-rsa
ssh-dss
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sha2-nistp521
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]

This is new feature in openssh-7.0 so remember that it doesn't have to work in older versions.

ssh-dsa key type is ssh-dss and it is disabled by default in this version.