How can I check the Mesos-DNS version?
You can check the Mesos-DNS version with
Note: We do not recommend upgrading Mesos-DNS independently of DC/OS. Use the version of Mesos-DNS that shipped with your version of DC/OS.
What if Mesos-DNS fails to launch?
Check that port 53 and port 8123 are available and not in use by other processes.
What if my Agent nodes cannot connect to Mesos-DNS?
Make sure that port 53 is not blocked by a firewall rule on your cluster.
It is possible that the Master nodes are not running. Run
sudo systemctl status dcos-mesos-dnsand
sudo journalctl -u dcos-gen-resolvconf.service -n 200 -ffor more information about Mesos-DNS errors.
How do I configure my DC/OS cluster to communicate with external hosts and services?
For DNS requests for hostnames or services outside the DC/OS cluster, Mesos-DNS will query an external nameserver. By default, Google’s nameserver with IP address 126.96.36.199 will be used. If you need to configure a custom external name server, use the
resolvers parameter when you first install DC/OS.
Important: External nameservers can only be set when you install DC/OS. They cannot be changed after installation.
To query the leading master node, always query
If you try to connect to
master.mesos using HTTP, you will be automatically redirected to the leading master node.
However, if you try to query or connect to
master.mesos using any method other than HTTP, the results will be unpredictable because the name will resolve to a random master node. For example, a service that attempts to register with
master.mesos may communicate with a non-leading master node and will be unable to register as a service on the cluster.