The v2 documentation for Kubernetes, both CRD and Ingress, explicitly discusses LetsEncrypt with HA and suggests CertManager as a solution. I have that in place and it seems to be working well.
I also have Docker Swarm deployments where I need to run Traefik CE in HA (one container per manager node) and I would like to use the LetsEncrypt functionality. The documentation does not explicitly say so, but I suspect the same issues with HA and LetsEncrypt exist for Traefik with Docker Swarm as for with Kubernetes. Is that correct?
If so, is there a suggested best practice for how to leverage the Traefik LetsEncrypt functionality in a HA configuration?
After reading the v2 documentation I wondered if using the dnsChallenge in a HA environment would work because the lego tool will not try to update an existing TXT record so there would be no race condition? I am open to doing the experiment to find out for myself, but if anybody already knows the answer I would be grateful for the information.