Multi-node¶
This tutorial shows how to install a 3-node MicroOVN cluster.
One big advantage of a multi-node cluster is that it provides redundancy (service failover). A 3-node deployment can tolerate up to one node failure.
Requirements¶
You will need three (virtual or physical) machines that can communicate with
each other over the network. They will be known here as node-1, node-2,
and node-3.
Install the software¶
Install MicroOVN on each of the designated nodes with the following command:
sudo snap install microovn
Initialise the cluster¶
On node-1, initialise the cluster:
microovn cluster bootstrap
Generate access tokens¶
On node-1, generate access tokens for the other two nodes (cluster members). These will be needed to join these nodes to the cluster.
Let this token be for node-2:
microovn cluster add node-2
The output will be a special string such as:
eyJuYW1lIjoibm9kZS0yIiwic2VjcmV0IjoiMzBlM....
Let this token be for node-3:
microovn cluster add node-3
Similarly, a string will be sent to the screen:
eyJuYW1lIjoibm9kZS0zIiwic2VjcmV0IjoiZmZhY....
Complete the cluster¶
Join node-2 and node-3 to the cluster using their assigned access tokens.
On node-2:
microovn cluster join eyJuYW1lIjoibm9kZS0yIiwic2VjcmV0IjoiMzBlM...
On node-3:
microovn cluster join eyJuYW1lIjoibm9kZS0zIiwic2VjcmV0IjoiZmZhY...
Now all three nodes are joined to the cluster.
Manage the cluster¶
You can interact with OVN using its native commands due to automatically created snap aliases, for example, to show the contents of the OVN Southbound database:
ovn-sbctl show
The cluster can be managed from any of its nodes.