cluster down all nodes. how to config auto start?

I have 2 nodes
IP node 1:
IP node 2:
I have completed the Percona XtraDB Cluster configuration
Then I shutdown node 1 and then node 2
But it didn’t start service PXC when I restart them
Please show me how to configure auto start

If you shutdown both nodes then you will need to re-bootstrap at least one of the node (preferably node2 since that is the last node that was up).

node2> service mysql bootstrap-pxc
node2> systemctl start mysql@bootstrap.service

Then once this node is up and in SYNCED state, start the other node normally:
node1> service mysql start
node1> systemctl start mysql