Issue:


You are unable to join Percol8UTM to an AD Domain and the below error is present in the system log.


Mar 22 19:55:09 percol8utmmail webmail: /system_authservers.php: The command '/usr/local/bin/net -s /var/etc/smb.conf ads join -Uadministrator%'password' -w AD.THEPACKETHUB.CO.ZA' returned exit code '255', the output was 'Failed to join domain: failed to find DC for domain AD.THEPACKETHUB.CO.ZA'


Mar 22 19:59:49 percol8utmmail webmail: /system_authservers.php: The command '/usr/local/bin/net -s /var/etc/smb.conf ads join -Uadministrator%'password' -w AD.THEPACKETHUB.CO.ZA' returned exit



Probable Causes:


1. The DNS server on Percol8UTM is not set to the IP address of the AD server and therefore Percol8UTM is unable to locate the host record for the AD Domain Controller.

2. The Percol8UTM AD settings is set with the incorrect realm.



Resolution:


1. Ensure that the Percol8UTM is configured to make use of at least one of the AD DNS servers in your environment for DNS resolution. 

2. Ensure that the Percol8UTM is not configured to make use of any other DNS servers other than your AD DNS servers.

3. Ensure the realm configured on Percol8UTM matches the realm of the AD Domain you are attempting to join.