Ispmanager 6 business documentation

Issues with DNS-server


This article provides solutions to the most common issues you may have when using ISPmanager Lite (Pro, Host).

DNS-server logs and files

FilesCentOSDebian, Ubuntu
PowerDNS configuration file/etc/pdns/pdns.conf/etc/powerdns/pdns.conf
PowerDNS domain zone records.
The records are kept in MySQL databases, a separate base for every name space.
The default name space is powerdns.The default name space is pdns.
BIND and PowerDNS logs/var/log/messages/var/log/syslog

Master DNS-server diagnostics

DNS server does not respond to request for domain zone

Make sure the DNS-server on the master server responds to requests for the domain zone:

dig <domain> @<IP address> ANY +short
View details

A response will look something like this:

dig @ ANY +short 2014041800 10800 3600 604800 86400
"v=spf1 ip4: a mx ~all"

The following response indicates that the DNS-server is not running:

dig domain.nam @ ANY +short
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.23.rc1.el6_5.1 <<>> domain.nam @ ANY +short
;; global options: +cmd
;; connection timed out; no servers could be reached

An empty response indicates that the DNS-server doesn't have information about the domain. Perhaps, it could not upload the domain zone. Open the log for more details.

Slave name server diagnostics

Checking connection with the DNS-server

Try to connect to port 53 of the master server through telnet:

telnet <IP address of the master server> 53

If you cannot connect, check the Firewall settings on the master and slave servers.

Checking domain zone transfer from the master to the slave server

Execute the command:

dig <domain> @<IP address> axfr
View details

The response should look like this:

dig @ axfr
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.23.rc1.el6_5.1 <<>> @ axfr
;; global options: +cmd		3600	IN	SOA 2014041800 10800 3600 604800 86400		3600	IN	NS		3600	IN	NS		3600	IN	TXT	"v=spf1 ip4: a mx ~all"		3600	IN	MX	10		3600	IN	A	3600	IN	A	3600	IN	A	3600	IN	A	3600	IN	A	3600	IN	A		3600	IN	SOA 2014041800 10800 3600 604800 86400

A possible cause: the file of the DNS-server domain zone in allow-transfer includes the private IP address, which is not accessible from the secondary server.