My understanding is that setting the Service type to LoadBalancer creates a new Azure Load Balancer and assigns an IP address to the Service. Does this mean that I can have multiple Services using port 80? If the app behind my Service (an ASP.NET Core app) can handle TLS and HTTPS why shouldn't I just use LoadBalancer's for any Service I want to expose to the internet?
What is the advantage of using an Ingress if I don't care about TLS termination (You can let Cloudflare handle TLS termination)? If anything, it slows things down by adding an extra hop for every request.
Some answers below mention that creating load balancers is costly. It should be noted that load balancers on Azure are free but they do charge for IP addresses of which they give you five for free. So for small projects where you want to expose up to five IP addresses, it's essentially free. Any more than that, then you may want to look ad usign Ingress.
Some answers also mention extra complexity if you don't use Ingress. I have already mentioned that Cloudflare can handle TLS termination for me. I've also discovered the external-dns Kubernetes project to create DNS entries in Cloudflare pointing at the load balancers IP address? It seems to me that cutting out Ingress reduces complexity as it's one less thing that I have to configure and manage. The choice of Ingress is also massive, it's likely that I'll pick the wrong one which will end up unmaintained after some time.
There is a nice article here which describe the differences on Service(Load Balancer) and Ingress.
In summary, you can have multiple Service(Load Balancer) in the cluster, where each application is exposed independently from each other. The main issue is that each Load Balancer added will increase the cost of your solution, and does not have to be this way, unless you strictly need this.
If multiple applications listen on port 80, and they are inside the container, there is no reason you also need to map it to the port 80 in the host node. You can assign it to any port, because the Service will handle the dynamic port mappings for you.
The ingress is best in this scenario, because you can have one ingress listing on port 80, and route the traffic to the right service based on many variables, like:
Ingress in not just for TLS termination, it is in simple terms a proxy\gateway that will control the routing to the right service, TLS termination is just one of the features.
No, you cant have multiple services listening on port 80, as load balancer wont know where to route them (ingress will, however). If you can affort to host each service on different port you could use load balancer. alternatively, if you have public ip for each service and different backend port on each service you can achieve this.
quote: The protocol and port combination you entered matches another rule used by this load balancer. The protocol and port combination of each load balancing rule and inbound NAT rule on a load balancer must be unique.
again, if you are a developer, you probably do not realize how much more convenient it is to manage certificate on ingress, and not on all individual containers that are supposed to be accessible