Jenkins : Host key verification failed while executing ssh

Question

I am trying to create a build with basic configuration on the slave node. Only command the needs to be executed from Execute shell option is doing ssh to the slave. While executing the build the following error is observed:

Building remotely on slave 1 in workspace /home/jenkins/workspace/slave job 1
[slave job 1] $ /bin/sh -xe /tmp/hudson4772532626468045261.sh
+ ssh jenkins@172.27.170.108
Pseudo-terminal will not be allocated because stdin is not a terminal.
Host key verification failed.
Build step 'Execute shell' marked build as failure

In order to solve the issue of Pseduo-Termial, added the option of -T while doing ssh, and still the same issue Host Key Verification failed :

Building remotely on slave 1 in workspace /home/jenkins/workspace/slave job 1
[slave job 1] $ /bin/sh -xe /tmp/hudson2830119741217409056.sh
+ ssh -T jenkins@172.27.170.108
Host key verification failed.

After googling out got to know that ssh keys needs to be added in localhost. Even verified that manually and no options for password were prompted while doing ssh. Below is the output:

jenkins@labadmin-VirtualBox:/root/RAGHU$ ssh jenkins@172.27.170.108
Welcome to Ubuntu 14.04.5 LTS (GNU/Linux 4.2.0-27-generic x86_64)

* Documentation:  https://help.ubuntu.com/

88 packages can be updated.
60 updates are security updates.
........
........
and reboot your system.
Last login: Fri Apr 14 14:46:50 2017 from 172.24.43.35
jenkins@RTPS-DCE-DV:~$

Please help in resolving these issues..

EDIT : Adding the ssh debug info:

jenkins@labadmin-VirtualBox:/root/RAGHU$ ssh -vvv jenkins@172.27.170.108
OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014
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 172.27.170.108 [172.27.170.108] port 22.
debug1: Connection established.
debug3: Incorrect RSA1 identifier
debug3: Could not load "/var/lib/jenkins/.ssh/id_rsa" as a RSA1 public key
debug1: identity file /var/lib/jenkins/.ssh/id_rsa type 1
debug1: identity file /var/lib/jenkins/.ssh/id_rsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_dsa type -1
debug1: identity file /var/lib/jenkins/.ssh/id_dsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ecdsa type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ecdsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ed25519 type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8 pat OpenSSH_6.6.1* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "172.27.170.108" from file "/var/lib/jenkins/.ssh/known_hosts"
debug3: load_hostkeys: found key type ECDSA in file /var/lib/jenkins/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
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
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: 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,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: 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-dss-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-dss-cert-v00@openssh.com,ssh-ed25519,ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,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: 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,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: first_kex_follows 0 
debug2: kex_parse_kexinit: reserved 0 
debug2: mac_setup: setup hmac-md5-etm@openssh.com
debug1: kex: server->client aes128-ctr hmac-md5-etm@openssh.com none
debug2: mac_setup: setup hmac-md5-etm@openssh.com
debug1: kex: client->server aes128-ctr hmac-md5-etm@openssh.com none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA 63:f8:4a:65:e2:44:f2:ba:aa:25:cd:01:81:ac:f3:07
debug3: load_hostkeys: loading entries for host "172.27.170.108" from file "/var/lib/jenkins/.ssh/known_hosts"
debug3: load_hostkeys: found key type ECDSA in file /var/lib/jenkins/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug1: Host '172.27.170.108' is known and matches the ECDSA host key.
debug1: Found key in /var/lib/jenkins/.ssh/known_hosts:1
debug1: ssh_ecdsa_verify: signature correct
debug2: kex_derive_keys
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: /var/lib/jenkins/.ssh/id_rsa (0x7f020b7d2f80),
debug2: key: /var/lib/jenkins/.ssh/id_dsa ((nil)),
debug2: key: /var/lib/jenkins/.ssh/id_ecdsa ((nil)),
debug2: key: /var/lib/jenkins/.ssh/id_ed25519 ((nil)),
debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred gssapi-keyex,gssapi-with-mic,publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /var/lib/jenkins/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug2: input_userauth_pk_ok: fp b3:76:7b:34:c7:dd:f8:21:07:f6:ec:19:ea:94:da:5a
debug3: sign_and_send_pubkey: RSA b3:76:7b:34:c7:dd:f8:21:07:f6:ec:19:ea:94:da:5a
debug1: key_parse_private2: missing begin marker
debug1: read PEM private key done: type RSA
debug1: Authentication succeeded (publickey).
Authenticated to 172.27.170.108 ([172.27.170.108]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug2: callback start
debug2: fd 3 setting TCP_NODELAY
debug3: packet_set_tos: set IP_TOS 0x10
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug1: Sending environment.
debug3: Ignored env XDG_VTNR
debug3: Ignored env XDG_SESSION_ID
debug3: Ignored env TERM
debug3: Ignored env SHELL
debug3: Ignored env VAULT_ADDR
debug3: Ignored env USER
debug3: Ignored env LS_COLORS
debug3: Ignored env SUDO_USER
debug3: Ignored env SUDO_UID
debug3: Ignored env USERNAME
debug3: Ignored env PATH
debug3: Ignored env MAIL
debug3: Ignored env PWD
debug1: Sending env LANG = en_IN
debug2: channel 0: request env confirm 0
debug3: Ignored env HOME
debug3: Ignored env SUDO_COMMAND
debug3: Ignored env XDG_SEAT
debug3: Ignored env SHLVL
debug3: Ignored env LANGUAGE
debug3: Ignored env LOGNAME
debug3: Ignored env LESSOPEN
debug3: Ignored env DISPLAY
debug3: Ignored env SUDO_GID
debug3: Ignored env LESSCLOSE
debug3: Ignored env COLORTERM
debug3: Ignored env XAUTHORITY
debug3: Ignored env _
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Welcome to Ubuntu 14.04.5 LTS (GNU/Linux 4.2.0-27-generic x86_64)

 * Documentation:  https://help.ubuntu.com/

88 packages can be updated.
60 updates are security updates.

......
......

and reboot your system.
Last login: Fri Apr 14 17:19:05 2017 from 172.24.43.35
jenkins@RTPS-DCE-DV:~$

EDIT 2 : Adding the failed debug info :

Building remotely on slave 1 in workspace /home/jenkins/workspace/slave job 1
[slave job 1] $ /bin/sh -xe /tmp/hudson8556503525790261529.sh
+ ssh -vvv jenkins@172.27.170.108
OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
Pseudo-terminal will not be allocated because stdin is not a terminal.
debug2: ssh_connect: needpriv 0
debug1: Connecting to 172.27.170.108 [172.27.170.108] port 22.
debug1: Connection established.
debug1: identity file /var/lib/jenkins/.ssh/id_rsa type -1
debug1: identity file /var/lib/jenkins/.ssh/id_rsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_dsa type -1
debug1: identity file /var/lib/jenkins/.ssh/id_dsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ecdsa type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ecdsa-cert type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ed25519 type -1
debug1: identity file /var/lib/jenkins/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8 pat OpenSSH_6.6.1* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: 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,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-dss-cert-v00@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,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: 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,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: 
debug2: kex_parse_kexinit: first_kex_follows 0 
debug2: kex_parse_kexinit: reserved 0 
debug2: mac_setup: setup hmac-md5-etm@openssh.com
debug1: kex: server->client aes128-ctr hmac-md5-etm@openssh.com none
debug2: mac_setup: setup hmac-md5-etm@openssh.com
debug1: kex: client->server aes128-ctr hmac-md5-etm@openssh.com none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA 63:f8:4a:65:e2:44:f2:ba:aa:25:cd:01:81:ac:f3:07
debug1: read_passphrase: can't open /dev/tty: No such device or address
Host key verification failed.

Possible duplicate of [Jenkins Host key verification failed](http://stackoverflow.com/questions/15174194/jenkins-host-key-verification-failed) — Jakuje, Apr 14 '17 at 11:14
In order to show that I have added the ssh keys properly, I have displayed the result when tried manually for ssh to the server. I don't see any issues with ssh manually. — Here_2_learn, Apr 14 '17 at 11:38
Are you sure you do it on the correct host and under the same user? For debugging purposes, it is helpful to add `-vvv` to see more debug information, that can come handy. — Jakuje, Apr 14 '17 at 11:42
added the log for failed attempt. and for more info adding this : jenkins@RTPS-DCE-DV:/dev$ ls -la /dev/tty crw-rw-rw- 1 root tty 5, 0 Apr 14 15:46 /dev/tty — Here_2_learn, Apr 14 '17 at 16:49

score 0 · Answer 1 · answered Apr 15 '17 at 17:23

0

In your log, you can notice one interesting thing:

Your manual run:

debug1: identity file /var/lib/jenkins/.ssh/id_rsa type 1

Your "automatic" run:

debug1: identity file /var/lib/jenkins/.ssh/id_rsa type -1

Similar issue is with the /var/lib/jenkins/.ssh/known_hosts. It exists in the first case, but not in the second one. This means you are running either on different system or the second case is somehow jailed in chroot or by other means separated from the rest of the filesystem (this is a good idea for running random code from jenkins).

Next steps are finding out how are the chroots for this user created and modify the known hosts inside this chroot. Or just go other ways of ignoring known hosts, such as ssh-keyscan, StrictHostKeyChecking=no or so.

answered Apr 15 '17 at 17:23

Jakuje

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Sorry, I didn't get what should be done next to find out the issue. Please let me know that do I need to what are the commands to be executed? – Here_2_learn Apr 16 '17 at 05:04
Finally able to solve the issue after editing /etc/sudoers file from jenkins ALL=(ALL:ALL) ALL to jenkins ALL=(ALL) NOPASSWD: ALL – Here_2_learn Apr 16 '17 at 06:10
That is completely unrelated to the problem you were describing (there was nowhere mentioned `sudo`) – Jakuje Apr 16 '17 at 07:10
Sorry for the confusion, the above comment has not resolved the issue. The main issue still exists. – Here_2_learn Apr 17 '17 at 10:22

score 0 · Answer 2 · answered Apr 19 '18 at 23:01

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Ssh tries to ask you

Are you sure you want to continue connecting (yes/no)?

This is because ssh fails without tty.

answered Apr 19 '18 at 23:01

Pavel Patrin

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score 0 · Answer 3 · answered Dec 18 '21 at 04:08

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Insert the following lines in Jenkins init script:

# Disable StrictHostKeyChecking
mkdir -p ~/.ssh && touch ~/.ssh/config
echo "StrictHostKeyChecking no" > ~/.ssh/config

answered Dec 18 '21 at 04:08

Joel Tenta

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score 0 · Answer 4 · answered May 21 '22 at 21:36

I arrived here when trying to move an existing resource from one of our servers to another. Everything was seemingly working on the old server but failed when I tried to move everything over to the new.

I was seeing something similar to the author when our CI (Bitbucket Pipelines in our case) was trying to connect - everything looked fine on the server side but it looked like the client was disconnecting:

debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:I1Jbni6WLT89FOUyYALAC+thfmPw4m9XBiXHFnlUaCQ
debug1: read_passphrase: can't open /dev/tty: No such device or address
Host key verification failed.

This thread was very helpful - I finally realized that maybe there was something on the client side rejecting the new server... It turns out on Bitbucket you need to register pipeline SSH keys under Repository Settings / Pipelines / SSH Keys. This section allows you to setup an SSH key as you'd expect.

BUT you also need to ensure you've updated the Known Hosts section. This is what I missed and once I added the fingerprint for the new host everything began working.

For what it's worth I think Joel's idea above would also work - I was going to try that next and I think it would be more universal than this Bitbucket specific approach to populate known hosts.

Jenkins : Host key verification failed while executing ssh

4 Answers4

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