Git Permission denied (publickey,gssapi-keyex,gssapi-with-mic)? - linux

Question

Client: OS Ubuntu, git-version 2.7.4.
Server: OS Centos , git-version 2.7.4.
I have a private ssh key in my client and public key in server.
I can use shell to enter my server(no password).
But can't push origin master !
sudo ssh -i /path/to/key/ -vT git#xxx.xx.xxx.xxx
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016 debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to xxx.xx.xxx.xxx [xxx.xx.xxx.xxx] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /home/whj/.ssh/whjwebsite type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/whj/.ssh/whjwebsite-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1 debug1: match: OpenSSH_6.6.1 pat OpenSSH_6.6.1* compat 0x04000000
debug1: Authenticating to xxx.xx.xxx.xxx:22 as 'git'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
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: none
debug1: kex: client->server cipher: chacha20-poly1305#openssh.com MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:aC1Ydp+6x8IP+TV5jEl7WwqW6sEycbznbfL09qON/OA
debug1: Host 'xxx.xx.xxx.xxx' is known and matches the ECDSA host key.
debug1: Found key in /root/.ssh/known_hosts:1
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-debug1: Next authentication method: gssapi-keyex
debug1: No valid Key exchange context
debug1: Next authentication method: gssapi-with-mic
debug1: Unspecified GSS failure. Minor code may provide more information No Kerberos credentials available
debug1: Unspecified GSS failure. Minor code may provide more information No Kerberos credentials available
debug1: Unspecified GSS failure. Minor code may provide more information debug1: Unspecified GSS failure. Minor code may provide more information No Kerberos credentials available
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/whj/.ssh/whjwebsite
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-debug1: No more authentication methods to try. Permission denied (publickey,gssapi-keyex,gssapi-with-mic).
'whjwebsite 'is my private key.
drwx------ .ssh/
-rw------- whjwebsite
server:sshd_config:
```
RSAAuthentication yes
PubkeyAuthentication yes
GSSAPIAuthentication yes
GSSAPICleanupCredentials no
UseDNS no
AddressFamily inet
PermitRootLogin yes
SyslogFacility AUTHPRIV
PasswordAuthentication no
ChallengeResponseAuthentication no
client:ssh_config
enter image description here

Answer 1

My 2 cents: on server side, disable GSSAPIAuthentication (i.e. SSO backed by Kerberos) unless you are using Active Directory authentication on Linux (with either Centrify or SSSD) inside a corporate firewall.
If you are indeed in a SSO scenario, but Single Sign-On does not work out of the box for some reason, then use client-side options to bypass Kerberos e.g.
ssh -o GSSAPIAuthentication=no -o GSSAPIKeyExchange=no