diff --git a/doc/source/install/multinode.rst b/doc/source/install/multinode.rst index fb28a055f2..e6ccd6dbd1 100644 --- a/doc/source/install/multinode.rst +++ b/doc/source/install/multinode.rst @@ -188,8 +188,23 @@ Kubernetes Node DNS Resolution ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ For each of the nodes to know how to reach Ceph endpoints, each host much also -have an entry for ``kube-dns``. Since we are using Ubuntu for our example, place -these changes in ``/etc/network/interfaces`` to ensure they remain after reboot. +have an entry for the ``kube-dns`` nameserver. That nameserver should be the +first one in ``/etc/resolv.conf``, followed by general-purpose nameservers. +A DNS search string such as the one below, along with the +``ndots:5`` option, will allow for OpenStack-Helm services to resolve one +another using short domain names. The ``timeout:1`` and ``attempts:1`` +options will ensure that, as the nameservers are used in order, lookups move +to the next one quickly when the ``kube-dns`` service is unavailable +(e.g. when rebooting the node). Example: + +:: + + admin@kubenode01:~$ cat /etc/resolv.conf + nameserver 10.96.0.10 # Kubernetes DNS Server + nameserver 8.8.8.8 # Upstream DNS Server + nameserver 8.8.4.4 # Upstream DNS Server + search openstack.svc.cluster.local svc.cluster.local cluster.local + options ndots:5 timeout:1 attempts:1 To do this you will first need to find out what the IP Address of your ``kube-dns`` deployment is: @@ -201,6 +216,12 @@ To do this you will first need to find out what the IP Address of your kube-dns 10.96.0.10 53/UDP,53/TCP 1d admin@kubenode01:~$ +You may need to take extra steps to persist these settings across reboots. +Since we are using Ubuntu for our example, the nameservers and search entries +should go in ``/etc/network/interfaces`` (see ``man 8 resolvconf``), +and the ``options`` line should be placed in +``/etc/resolvconf/resolv.conf.d/base``. + Now we are ready to continue with the Openstack-Helm installation. Openstack-Helm Preparation