Comment on Multiple Kubernetes Services Using Same Port Without SNI
wireless_purposely832@lemmy.world 3 weeks agoI am unsure if I understood everything correctly, but I believe I am already doing everything that you mentioned. I followed the Kube-VIP’s ARP daemonset’s documentation. The leader election works. I am not using Kube-VIP for load balancing though. Instead, I am using Traefik, which is using the same IP address that was assigned to the control plane during both k3s’s and Kube-VIP’s setup. However, I am unable to get any additional VIP addresses to properly route to Traefik.
Even if I did get the additional VIP addresses working, I think I still have one last issue to overcome. I can control the local network’s DNS so that service#1 is assigned VIP#1 and service#2 assigned VIP#2. However, how would this be handled for traffic received externally? If the external/public DNS has service#1 and service#2 assigned to the network’s public IP address, both service’s traffic would be received by the router/firewall on port 22. The router/firewall could forward traffic on port 22 to (presumably) a single IP address, which would only allow service#1 or service#2 (but not both) to receive traffic publicly, correct?
simonmicro@programming.dev 3 weeks ago
Ah yes, I see. Because TCP has no SNI built-in this is not really possible.
You could try IPv6, as within even a single /64 routable prefix you can choose the address section freely. Also take a look at overlay-vpn solutions like Netbird: They allow you to offer you multiple clients, which you could use to assign multiple IPv4 to your server and then routing them differently…
wireless_purposely832@lemmy.world 3 weeks ago
I had not thought about using IPv6 for this. It’s definitely something that I would need to research more as I know that this would expose my attack surface and may require an overhaul of the network (or at least a very thorough review).
I’m not sure I understand the concern about Traefik. I am using it as a reverse proxy and forcing HTTPS for all applicable services (which unfortunately does not apply to this particular situation). I am honestly a little confused about the control plane, tls-san, gateway, load balancer, ingress, etc. and how they all work together. I may not be using Traefik as the Load Balancer and instead have Kube-VIP as the LoadBalancer. I did not configure Kube-VIP any particular way for Load Balancing, but I did configure Traefik with a few Load Balancer specific options. When I tried to setup Kube-VIP with the additional IP addresses for load balancing, I was unable to get k3s to work correctly so I assumed that Traefik was my Load Balancer instead of Kube-VIP.