O SSH não está escolhendo uma correspondência mais específica de ~ / .ssh / config

Question

Eu tenho os seguintes valores de configuração no meu arquivo ~/.ssh/config :

Host *-lk
     User root

Host beta-lk
     Hostname beta.*****.com

Host accounts-lk
     Hostname accounts.*****.com

Host demo-lk
     Hostname demo.*****.com

Host central1-lk
     Hostname central-api-1.*****.com

Host central2-lk
     Hostname central-api-2.*****.com
     User ubuntu
     IdentityFile ~/.ssh/*****.aws.pem

O central2-lk foi criado apenas hoje. Quando eu tento ssh para central2-lk como host:

➜ ssh -v central2-lk
OpenSSH_7.4p1 Debian-10+deb9u3, OpenSSL 1.0.2l  25 May 2017
debug1: Reading configuration data /home/hjpotter92/.ssh/config
debug1: /home/hjpotter92/.ssh/config line 17: Applying options for *-lk
debug1: /home/hjpotter92/.ssh/config line 41: Applying options for central2-lk
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to central-api-2.*****.com [XXXX.XXX.XXX.XX] port 22.
debug1: Connection established.
debug1: key_load_public: No such file or directory
debug1: identity file /home/hjpotter92/.ssh/*****.aws.pem type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/hjpotter92/.ssh/*****.aws.pem-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.4p1 Debian-10+deb9u3
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu2.1
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu2.1 pat OpenSSH* compat 0x04000000
debug1: Authenticating to central-api-2.*****.com:22 as 'root'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: algorithm: [email protected]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:3lqRdK0W0zOqWIW0bSkn9vMAFbXbEiRdY9cgcvDZ4ZM
debug1: Host 'central-api-2.*****.com' is known and matches the ECDSA host key.
debug1: Found key in /home/hjpotter92/.ssh/known_hosts:36
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/hjpotter92/.ssh/*****.aws.pem
debug1: Server accepts key: pkalg rsa-sha2-512 blen 279
debug1: Authentication succeeded (publickey).
Authenticated to central-api-2.*****.com ([XXXX.XXX.XXX.XX]:22).
debug1: channel 0: new [client-session]
debug1: Requesting [email protected]
debug1: Entering interactive session.
debug1: pledge: network
debug1: client_input_global_request: rtype [email protected] want_reply 0
debug1: Remote: Port forwarding disabled.
debug1: Remote: Agent forwarding disabled.
debug1: Remote: X11 forwarding disabled.
debug1: Remote: Forced command.
debug1: Remote: Port forwarding disabled.
debug1: Remote: Agent forwarding disabled.
debug1: Remote: X11 forwarding disabled.
debug1: Remote: Forced command.
debug1: Sending environment.
debug1: Sending env LANG = en_IN
debug1: Sending env LC_CTYPE = en_IN
debug1: Sending env LC_ALL = en_IN.UTF-8
Please login as the user "ubuntu" rather than the user "root".

debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: client_input_channel_req: channel 0 rtype [email protected] reply 0
debug1: channel 0: free: client-session, nchannels 1
Connection to central-api-2.*****.com closed.
Transferred: sent 3204, received 3420 bytes, in 10.2 seconds
Bytes per second: sent 313.3, received 334.5
debug1: Exit status 0
%

➜ ssh ubuntu@central2-lk
Welcome to Ubuntu 16.04.2 LTS (GNU/Linux 4.4.0-1013-aws x86_64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage

  Get cloud support with Ubuntu Advantage Cloud Guest:
    http://www.ubuntu.com/business/services/cloud

140 packages can be updated.
2 updates are security updates.


*** System restart required ***
Last login: Tue Jul 31 17:45:39 2018 from XXXX.XX.XX.XXX
ubuntu@ip-172-31-20-247:~$ logout
Connection to central-api-2.*****.com closed.

Por que minha definição de configuração User ubuntu para central2-lk está sendo ignorada?

    

Answer 1

É porque você tem Host *-lk como a primeira entrada na sua configuração. Como diz em man ssh-config :

For each parameter, the first obtained value will be used.
(...)
PATTERNS
     A pattern consists of zero or more non-whitespace characters, ‘*’ (a wildcard that matches zero or more char‐
     acters), or ‘?’ (a wildcard that matches exactly one character).  For example, to specify a set of declara‐
     tions for any host in the ".co.uk" set of domains, the following pattern could be used:

           Host *.co.uk