Reverse DNS lookup of Linux system not function with Windows Active Directory

My Linux system (KUbuntu 20.04 KDE) is connected with Windows Active Directory.

I am able to ping the IP address of Linux box from the network PCs of the Domain. I can see the hostname of my Linux box as well using the ping -a command.

The problem is that, when I am pinging the hostname instead of IP address, then it's not getting a response from the Linux box.

1 Answer

Diagnosis:

• Get full domain name (full-domain-name) of your Active Directory. Usually it is somedomain.local or somedomain.lan etc.
• Get Linux box supposed FQDN, i.e fully qualified domain name linuxbox-name.full-domain-name. Example: mybox01.somedomain.lan
• Check DNS records.

1. Check of DNS A-record:

On Windows machine use

nslookup linuxbox-name.full-domain-name 

On Linux use

dig linuxbox-name.full-domain-name 

Check answer/answer section. If no valid IP address is listed, it means no DNS record exists for such name in domain.

2. Check of DNS PTR-record:

On Windows machine use

nslookup linuxbox-IP-address 

On Linux use

dig -x linuxbox-IP-address 

In case you get valid FQDN device name in DNS server response, compare it with your supposed FQDN in first test above, correct the name and repeat the first DNS check.

In case both checks are negative, your linuxbox does not have DNS records and its name cannot be used for network communication.

Possible solutions: Ask domain administrator for setting to create DNS A-record automatically by DHCP server if device is connected to network. Or ask him for DHCP static reservation for your device (MAC address - IP address) and for related DNS record.