Login as domain user fails in Linux

Question

Using pbis, joined a Linux (Ubuntu 14.04) node to the domain successfully.

# /opt/pbis/bin/get-status
LSA Server Status:

Compiled daemon version: 8.2.1.2979
Packaged product version: 8.2.2979.68390
Uptime:        0 days 20 hours 50 minutes 29 seconds

[Authentication provider: lsa-activedirectory-provider]

Status:        Online

It's also listing all the domain users as expected when we run getent passwd.

# getent passwd ttuser
ttuser:x:1124089581:1124073985:Test User:/home/<domain>/ttuser:/bin/bash

But when we try to login as domain user either through su or ssh it's failing with pam authentication failure.

When tried to login from the same machine using su:

su[7024]: pam_unix(su:auth): check pass; user unknown
su[7024]: pam_unix(su:auth): authentication failure; logname=ubuntu uid=1000 euid=0 tty=/dev/pts/1 ruser=ubuntu rhost=
su[7024]: pam_authenticate: Authentication failure
su[7024]: FAILED su for <Domain>\ttuser by ubuntu
su[7024]: - /dev/pts/1 ubuntu:<Domain>\ttuser

When tried to login from different machine using ssh:

sshd[7031]: error: Could not load host key: /etc/ssh/ssh_host_ed25519_key
sshd[7038]: pam_unix(sshd:auth): check pass; user unknown
sshd[7038]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=ip-172-21-3-42.eu-west-1.compute.internal
sshd[7031]: error: PAM: Authentication failure for <Domain>\\ttuser from ip-172-21-3-42.eu-west-1.compute.internal