docs/usecases/contiv/CUSTOM_MGMT_NETWORK.rst

Setting Up a Custom Management Network on Multi-Homed Nodes
===========================================================

If the interface you use for Kubernetes management traffic (for example,
the IP address used for ``kubeadm join``) is not the one that contains
the default route out of the host, then you need to specify the
management node IP address in the Kubelet config file. Add the following
line to: (``/etc/systemd/system/kubelet.service.d/10-kubeadm.conf``):

::

   Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false --node-ip=<node-management-ip-address>"

Example
-------

Consider a 2 node deployment where each node is connected to 2 networks
- ``10.0.2.0/24`` and ``192.168.56.0/24``, and the default route on each
node points to the interface connected to the ``10.0.2.0/24`` subnet. We
want to use subnet ``192.168.56.0/24`` for Kubernetes management
traffic. Assume the addresses of nodes connected to ``192.168.56.0/24``
are ``192.168.56.105`` and ``192.168.56.106``.

On the ``192.168.56.105`` node you add the following line to
``10-kubeadm.conf``:

::

   Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false --node-ip=192.168.56.105"

On the ``192.168.56.106`` node you add the following line to
``10-kubeadm.conf``:

::

   Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false --node-ip=192.168.56.106"