IP Port Redirection - port

I have a silverlight->server communication system up that uses port 4530 among others. I've used no-ip.org to redirect traffic to my home server. Is there anyway to use no-ip (or is there another service like it?) to allow me to ping off an ip at port 4530 etc, and send it to my dynamic ip?

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How does docker-engine handle outgoing and incoming traffic from/to multiple containers?

I currently have about 5 webserver running behind a reverse proxy. I would like to use an external AD to authentificate my users with the ldap protocol. would docker-engine be able to differentiate between each container by itself ?
My current understanding is that it wouldn't be possible without having a containerized directory service or without exposing different port for each container but I'm having doubts. If I ping an external server from my container I'm able to get a reply in that same container without issue. how was the reply able to reach the proper container ?. I'm having trouble understanding how it would be different for any other protocol but then at the same time a reverse proxy is required for serving the content of multiple webservers. If anyone could make it a bit clearer for me I'd greatly appreciate it.
After digging a bit deeper I have found what I was looking for.
Any traffic originating from a container will get routed automatically by docker on a default network with the use of IP masquerading (similar to NAT) through iptables. The way it works is that the packets from the container will get stripped of the container IP address and replaced by the host ip address. The original ip address will be remembered until the tcp session is over. Then the traffic will go to the destination and any reply will be sent back to the host. the reply packets will get stripped of the host ip and sent to the proper container. This is why you can ping another server from a container and get a reply in that same container.
But obviously it doesn't work for incoming traffic to a webserver because the first step is the client starting a session with the webserver. That's why a reverse proxy is required.
I may be missing a few things and may be mistaken about some others but this is the general idea.
TLDR: outgoing traffic (and any reply ) will get routed automatically by docker, you will have to use a reverse proxy to route incoming traffic to multiple container.

Docker server networking - reject incoming connections but allow outgoing

We use Docker containers to deploy multiple small applications on our servers that are reachable on the public internet. Some of the services need to communicate to each other, but are deployed on different servers, due to different hardware requirements (the servers are on different network and different IP).
Q: What would be the best way to configure blocking of incoming requests to SERVER:PORT except for some allowed IPs and at the same time allow all outgoing connections of the Docker containers?
Two major things we played with and tried out to get them working:
Bound Docker port mappings to 127.0.0.1 and route every traffic through an nginx. This is really config heavy and some infrastructure components aren't possible to proxy via http(s), so we need to add them to nginx.conf stream-server block and therefore open a port on the server (that is accessible by everyone).
Use iptables to restrict access to the published ports. So something like this: iptables -A INPUT -I DOCKER-USER -p tcp -i eth0 -j DROP. But this also have 2 major downfalls. First it seems that it's quite hard to allow multiple IP adresses in such a construct and on the other hand this approach seems to block our docker outgoing connections (to the internet) as well. E. g.: After we activated it a ping google.com from within a docker container was rejected.
Not sure I get this. In term of design, what is available to the external world is in a DMZ or published through an API gateway.
Your docker swarm/kubernetes cluster shall not be accessible directly through the internet or only the API gateway or the application on the DMZ.
So quite likely your docker server shall not be accessible directly. And even if that is the case, if you don't explicitely export a port to the host/outside of the cluster, it stay restricted to the virtuals networks of docker to allow cross container communication.

IIS local IP access externally with public IP

I have an ASP.Net MVC project that is running under IIS. I can reach it using local IP and port. I bind it with my IP and port.
What should I do to reach it with my public IP and port like http://PUBLICIP:PORT
When I try to reach it says connection error with code 502.
This is what I tried so far.
Adding my local IP to router's DMZ Adding
Port forwarding with port and my local IP
Add inbound and outbound rules to Firewall, inbound rules allow edge
traversal.
Turning off firewall, windows defender etc.
Do I need any features to install when I try to reach IIS externally?
Thanks all.

NAT (Redirect) outgoing traffic to a specific port

I'm trying to establish a connection with a diameter server. That server has a restriction parameter of "peer port"
Which means source port of my outgoing traffic should be restricted to a specific port.
Since I'm using an erlang diameter client, I didn't find any parameter to specify the outgoing port. It will initiate the connection with a random port to the destination ip:port.
Is there a way to translate my outgoing traffic to that ip locally to a specific port from linux?, so that the external server will see my source port as the allowed port.
You should apply a NAT at the sender side. Read this thread, it explains how to do it with iptables.

What is my web service ports to be allowed in the firewall?

Due to a virus in the system, one of our clients have made access to internet restricted in their server. We use two web services data on this server (both use a SOAP API).
The client company is asking me for the ports on the firewall they should leave open so we could be able to use those web services only. I'm not good at networks. So how can I get those information?
I need the port or any address from my two services so that they let them pass through the firewall.
I'm not sure I understand the question, but most web services receive connections on one of:
80 (http)
443 (https)
8080 (http)
Most firewalls client should be configured to allow outbound connections to these.
Server firewall MUST be configured to allow inbound connections on one of these (or some other pre-arranged non-standard port).
To work out what ports your existing web server is actually using:
how to investigate ports opened by a certain process in linux?
Its most likely, 80, 443, or 8080.

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