ssh : Permission denied (publickey,gssapi-with-mic)

i'm use centos 5.9. after installing gitlab by this link ssh not working. before install gitlab ssh correctly working. i'm using this server localy and other services such as elastix and apache,mysql installed on server.

appeare this error :

OpenSSH_6.9p1 Ubuntu-2ubuntu0.1, OpenSSL 1.0.2d 9 Jul 2015
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 192.168.88.23 [192.168.88.23] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_rsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
                                        debug1: Local version string SSH-2.0-OpenSSH_6.9p1 Ubuntu-2ubuntu0.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH_4* compat 0x00000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 192.168.88.23:22 as 'root'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: [email protected],[email protected],ssh-rsa,[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,ssh-dss
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[email protected],[email protected],[email protected],[email protected],hmac-md5,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: none,[email protected],zlib
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: first_kex_follows 0 
debug2: kex_parse_kexinit: reserved 0 
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[email protected]
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[email protected],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: none,[email protected]
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: first_kex_follows 0 
debug2: kex_parse_kexinit: reserved 0 
debug1: kex: server->client aes128-ctr hmac-sha1 none
debug1: kex: client->server aes128-ctr hmac-sha1 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<7680<8192) sent
debug1: got SSH2_MSG_KEX_DH_GEX_GROUP
debug2: bits set: 3111/6144
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: got SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: ssh-rsa SHA256:7J6JOe94H9PedNKlx6yG/wMy6ZYC8iB74WdOVGDgY7A
debug1: Host '192.168.88.23' is known and matches the RSA host key.
    debug1: Found key in /root/.ssh/known_hosts:1
debug2: bits set: 3102/6144
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /root/.ssh/id_rsa ((nil)),
debug2: key: /root/.ssh/id_dsa ((nil)),
debug2: key: /root/.ssh/id_ecdsa ((nil)),
debug2: key: /root/.ssh/id_ed25519 ((nil)),
debug1: Authentications that can continue: publickey,gssapi-with-mic
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

debug2: we did not send a packet, disable method
debug1: Next authentication method: publickey
debug1: Trying private key: /root/.ssh/id_rsa
debug1: Trying private key: /root/.ssh/id_dsa
debug1: Trying private key: /root/.ssh/id_ecdsa
debug1: Trying private key: /root/.ssh/id_ed25519
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
Permission denied (publickey,gssapi-with-mic).

I had the same issue while using vagrant. So from my Mac I was trying to ssh to a vagrant box (CentOS 7)

Solved it by amending the /etc/ssh/sshd_config PasswordAuthentication yes then re-started the service using sudo systemctl restart sshd

Hope this helps.

Setting 700 to .ssh and 600 to authorized_keys solved the issue.

chmod 700 /root/.ssh
chmod 600 /root/.ssh/authorized_keys

Setting PasswordAuthentication to yes, is not the best way to go , is not as secure as using private and public keys for authentication !

First make sure that that you have the fallowing permissions set, on the server side.

First check your home dir (SERVER SIDE)

[vini@random ~]$ ls -ld ~

drwx------. 3 vini vini 127 Nov 23 15:29 /home/vini

if it is not like this, run

chmod 0700 /home/your_home

Now check .ssh folder

[vini@random ~]$ ls -ld  /home/vini/.ssh/

drwx------. 2 vini vini 29 Nov 23 15:28 /home/vini/.ssh/

if it is not looking like this, run

chmod 0700 /home/your_home/.ssh

now make sure that authorized_keys looks like this

[vini@venon ~]$ ls -ld  /home/vini/.ssh/authorized_keys 

-rw-------. 1 vini vini 393 Nov 23 15:28 /home/vini/.ssh/authorized_keys

or just run

chmod 0600 /home/your_home/.ssh/authorized_keys

After that go to /etc/ssh/sshd_config

For best security set

PermitRootLogin no

PubkeyAuthentication yes

keep as yes for testing purposes

PasswordAuthentication yes

Make sure that

ChallengeResponseAuthentication no

Comment those lines for GSSAPI

# #GSSAPIAuthentication yes
# #GSSAPICleanupCredentials no

Make sure that is set to UsePAM yes

UsePAM yes

now restart sshd service

systemctl restart sshd 

on the client side

cd /home/your_home/.ssh

generate new keys; setting a password is optional but is a good idea

ssh-keygen -t rsa -b 2048  

copy pub key to your server

ssh-copy-id -i id_rsa.pub user_name@server_ip 

start ssh agent 

eval $(ssh-agent)

ssh-add /home/user/.ssh/your_private_key

now your are good to go !

ssh user_name@server_ip

if everything works just fine

make a backup of your private key and then deny PasswordAuthentication

PasswordAuthentication no 

Restart you server

now anyone trying to ssh into your server, without your keys should get

vini@random: Permission denied (publickey).

keep script kids away from your business, and good luck

As everybody else has already said you need to edit /etc/ssh/sshd_config and change PasswordAuthentication no to PasswordAuthentication yes

I ran into this problem setting up a Vagrant box - so therefore it makes sense to script this and do it automatically in a shell provisioner:

sudo sed -i 's/PasswordAuthentication no/PasswordAuthentication yes/g' /etc/ssh/sshd_config;

sudo systemctl restart sshd;

According to the line debug1: Authentications that can continue: publickey,gssapi-with-mic , ssh password authentication is disabled and apparently you are not using public key authentication.

Login to your server using console and open /etc/ssh/sshd_config file with an editor with root user and look for line PasswordAuthentication then set it's value to yes and finally restart sshd service.