Recently we decided update our EC2 instances to Ubuntu 14.04.
We had simple Chef recipe based on different walk-through.
Joining to domain with
net ads join dnscreate@AWS.DOMAIN.COM
kerberos_kinit_password dnscreate@AWS.DOMAIN.COM failed: Cannot contact any KDC for requested realm
Same recipe worked with test kitchen. I spent couple days trying to find the reason. It appeared that winbind started to use UDP 88 instead of TCP 88. I didn’t find that in changelog, so beware.