我可以SSH到OpenStack实例，但是Ansible不能-它有什么不同？

Question

I've created an Ubuntu instance in OpenStack and retrieved the pem file to allow me to ssh into it from my Control machine. In total I have just two machines: My Control machine running Ubuntu and with Ansible 2.0.0.2 installed, and my Openstack instance that is also running Ubuntu.

From that control machine, I can ssh in using:

ssh -i /home/lovea/.ssh/ggcloud-keypair.pem ubuntu@192.168.138.107

This works - Without any additional keystrokes, I'm logged in on the OpenStack instance.

But I want to use Ansible - running on this same Control machine - to provision the Ubuntu instance. In /etc/ansible/ansible.cfg I've set the private key file to use the same one as I've been using to ssh. I then try to ping the Openstack instance using the following Ansible command:

ansible -vv --become-user ubuntu -i '192.168.138.107,' all -m ping

As I understand it, Ansible should try to connect as user ubuntu using the same ssh credentials. However, the response I get is:

192.168.138.107 | UNREACHABLE! => {
    "changed": false,
    "msg": "ERROR! SSH encountered an unknown error during the connection. We recommend you re-run the command using -vvvv, which will enable SSH debugging output to help diagnose the issue",
    "unreachable": true
}

As instructed, I reran this with -vvvv but there's a lot of output:

Using /etc/ansible/ansible.cfg as config file
Loaded callback minimal of type stdout, v2.0
<192.168.138.107> ESTABLISH SSH CONNECTION FOR USER: None
<192.168.138.107> SSH: EXEC ssh -C -vvv -o ControlMaster=auto -o ControlPersist=60s -o 'IdentityFile="/home/lovea/.ssh/ggcloud-keypair.pem"' -o KbdInteractiveAuthentication=no -o PreferredAuthentications=gssapi-with-mic,gssapi-keyex,hostbased,publickey -o PasswordAuthentication=no -o ConnectTimeout=10 -o ControlPath=/home/lovea/.ansible/cp/ansible-ssh-%h-%p-%r -tt 192.168.138.107 '( umask 22 && mkdir -p "$( echo $HOME/.ansible/tmp/ansible-tmp-1465459787.48-123588424864170 )" && echo "$( echo $HOME/.ansible/tmp/ansible-tmp-1465459787.48-123588424864170 )" )'
192.168.138.107 | UNREACHABLE! => {
    "changed": false,
    "msg": "ERROR! SSH encountered an unknown error. The output was:\nOpenSSH_7.2p2 Ubuntu-4ubuntu1, OpenSSL 1.0.2g-fips  1 Mar 2016
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: auto-mux: Trying existing master
debug1: Control socket \"/home/lovea/.ansible/cp/ansible-ssh-192.168.138.107-22-lovea\" does not exist
debug2: resolving \"192.168.138.107\" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to 192.168.138.107 [192.168.138.107] port 22.
debug2: fd 3 setting O_NONBLOCK
debug1: fd 3 clearing O_NONBLOCK
debug1: Connection established.
debug3: timeout: 9999 ms remain after connect
debug1: key_load_public: No such file or directory
debug1: identity file /home/lovea/.ssh/ggcloud-keypair.pem type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/lovea/.ssh/ggcloud-keypair.pem-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu1
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu1
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu1 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.138.107:22 as 'lovea'
debug3: hostkeys_foreach: reading file \"/home/lovea/.ssh/known_hosts\"
debug3: record_hostkey: found key type ECDSA in file /home/lovea/.ssh/known_hosts:12
debug3: load_hostkeys: loaded 1 keys from 192.168.138.107
debug3: order_hostkeyalgs: prefer hostkeyalgs: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
debug3: send packet: type 20
debug1: SSH2_MSG_KEXINIT sent
debug3: receive packet: type 20
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: zlib@openssh.com,zlib,none
debug2: compression stoc: zlib@openssh.com,zlib,none
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,zlib@openssh.com
debug2: compression stoc: none,zlib@openssh.com
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug1: kex: algorithm: curve25519-sha256@libssh.org
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: zlib@openssh.com
debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: zlib@openssh.com
debug3: send packet: type 30
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug3: receive packet: type 31
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:nj0kaJqxstRTaw8TFFAL7Xm/PiNoFjrD3I+EN0ghlHs
debug3: hostkeys_foreach: reading file \"/home/lovea/.ssh/known_hosts\"
debug3: record_hostkey: found key type ECDSA in file /home/lovea/.ssh/known_hosts:12
debug3: load_hostkeys: loaded 1 keys from 192.168.138.107
debug1: Host '192.168.138.107' is known and matches the ECDSA host key.
debug1: Found key in /home/lovea/.ssh/known_hosts:12
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug2: set_newkeys: mode 0
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /home/lovea/.ssh/ggcloud-keypair.pem ((nil)), explicit
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey
debug3: start over, passed a different list publickey
debug3: preferred gssapi-with-mic,gssapi-keyex,hostbased,publickey
debug3: authmethod_lookup publickey
debug3: remaining preferred: ,gssapi-keyex,hostbased,publickey
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/lovea/.ssh/ggcloud-keypair.pem
debug3: sign_and_send_pubkey: RSA SHA256:hihJQ4rsUcRl5JCc+TxubT3QO0qumD4SYL9GgABTaaQ
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
Permission denied (publickey).
",
    "unreachable": true
}

Seems to be that it doesn't like the ssh key. All I can think is that become isn't actually making Ansible try to connect as user ubuntu but is an instruction to perform once connected. Is this right? Is there some way I can connect as ubuntu , or do I need root access here?

Answer 1

As you've worked out, the become_user is for what user to su to once you are connected.

To change the user that you connect as you should use the ansible_user variable in your group or host vars in an inventory.

If you want to specify the connection user as a command line argument then you can use -u or --user .

Answer 2

Within the Ansible config file ( /etc/ansible/ansible.cfg by default), there's a commented-out option named remote_user . This can be set to something other than root in order to have Ansible connect as that user.