Portainer - OAuth conf. with multiple cluster nodes

Question

I've installed 3 nodes with Docker Swarm and Portainer:

• node1.int.org
• node2.int.org
• node3.int.org

Portainer uses Google Credential to authenticate each users.

The problem is that into the Redirect URL I can specify only one node (in the image below, node1.int.org ). If the node1.int.org die, and I use node2.int.org or node3.int.org to login, the redirect doesn't work!

What is the best practice to solve this problem?

Thank you

Answer 1

You create DNSRR records: swarm.int.org A IP1 swarm.int.org A IP2 *.swarm.int.org CNAME swarm.int.org

and then use "swarm.int.org" in place of "node1.int.org" when addressing swarm hosted services.

Bonus Point 1

Use Traefik to handle ssl offloading, so "https://swarm.int.org" can be used to connect to Portainer on the swarm.

Bonus Point 2

Use keepalived or similar to allocate a pool of VIPs and map the DNSRR entries to those. This means even if nodes go down the IPs and thus DNS entries keep routing to healthy nodes.