Configuring Mesos-DNS

About this task

After installing Mesos-DNS on its master node, configure Mesos-DNS by updating values in the config-dns.json file on the node where Mesos-DNS is installed and update the /etc/resolv.conf file on every node in the cluster.

NOTE: The Mesos-DNS mapr-mesos-dns package can be installed on any node that is designated as its master.

Procedure

On the node where Mesos-DNS is installed, update the resolvers value in /opt/mapr/mesos-services/mesos-services-0.1/conf/config-dns.json file.
Resolvers: A comma separated list with the IP addresses of external DNS servers that Mesos-DNS will contact to resolve any DNS requests outside the domain. This value is currently set to MapR DNS.
On every node in the cluster, update the /etc/resolv.conf file to include the nameservers (IP address) of the nodes where DNS is installed. Format: nameserver <IP address of the DNS server>.
IMPORTANT: The first nameserver specified in the /etc/resolv.conf file must be the IP address where Mesos-DNS is installed. This is to prevent issues associated with slow interconnectivity.
In the following example, 10.10.100.16 is the Mesos-DNS IP address:
```
vi /etc/resolv.conf

nameserver 10.10.100.16
nameserver 10.10.1.10
nameserver 12.250.1.3
```

Restart Mesos-DNS.

maprcli node services -name mesos-dns -action restart -nodes <node>