Reverse Proxy Port Forwarding
Reverse Proxy Deployments – Pipeline Pilot
Reverse Proxy Deployments
Reverse Proxy Features
Port forwarding is the process of intercepting traffic bound for a certain IP/port combination and redirecting it to a different IP and/or port. This redirection may be accomplished by an application running on the destination host, or it may be performed by intermediate hardware, like a router, reverse proxy server, or firewall.
A reverse proxy server is a backwards proxy server. It acts as an intermediary for clients that want to access a web site by forwarding requests. A reverse proxy can lower the server’s workload by redirecting requests to other similar servers via load balancing. Reverse proxies can also terminate SSL connections, which offloads SSL processing from the primary servers.
Reverse proxies and port forwarding firewalls are supported on both Windows and Linux. Due to the differences in paths, only one type of operating system can be deployed across the enterprise.
Guidelines
The primary requirement for port forwarding is that the forwarder preserves the original host header from the HTTP request. This also applies to load balancers. For most hardware implementations, this is not an issue as hardware should be protocol-independent. When using Apache as a reverse proxy, it’s necessary to edit the configuration to ensure that it preserves host headers.
Configuring a Reverse Proxy
When configuring for operation behind a reverse proxy, use a single port on the reverse proxy (SSL only) and terminate the SSL connection at the reverse proxy. This applies to any server running behind a port translating firewall, reverse proxy, or load balancer. (For details, see Configuring a Single Port Operation. )
To configure support for a reverse proxy:
1.
Go to Setup > Reverse Proxy and Load Balancing.
2.
In Full Name, enter the fully qualified domain name for your reverse proxy.
3.
In Aliases, enter any alias names for the reverse proxy, such as unqualified host or IP address.
4.
In Reverse Proxy Ports, specify the ports that will be forwarded to your Pipeline Pilot Server.
5.
To use SSL only, leave the HTTP Port field blank.
6.
If you are configuring for load balancing, check Load Balanced.
7.
Click Save.
See Also: Load Balancing Deployments | Server Deployments Overview
Difference between Reverse Proxy and Port Forwarding
While both methods might look similar, they are entirely different technically.
A proxy accepts a socket connection and fulfills the client request in some way or other. Usually, it creates its own request to the indicated server.
The by far most common example is an HTTP proxy that accepts HTTP requests from clients, uses its own HTTP request to retrieve the page/object, and then forwards the data to the client. Proxies can even translate application layer protocols (e. g. FTP over HTTP proxy) but they are always application-specific which makes them application-aware as well. Proxies were widely used for private-to-public Internet access before NAT become common. They can also be used for caching or deeper insight into the application protocol (application-layer gateway, malware scan, content filtering,… ).
A reverse proxy is used the other way around: public access for servers within private LANs. Since a proxy understands the application protocol, it can be used as a single entry point for multiple exposed servers, especially with HTTP. A reverse proxy can have multiple functions, including
caching
load balance across a number of backing servers
port sharing (multiple web servers are accessed using the same public IP address and transport-layer port number, distinguished by host header)
offloading SSL to the proxy
application-layer gateway/filtering
Port forwarding is another term for destination NAT aka reverse NAT, sometimes also virtual IP: a router translates a packet’s public destination address to the actual private address to enable access from the Internet to privately addressed servers. In contrast to a proxy, a NAT router is not aware of the application protocol that’s currently used. It only translates IP addresses and possibly transport-layer (L4) port numbers.
That way, it isn’t possible to enable public access to multiple private servers using a single public IP address and L4 port – you need to either have multiple public addresses or use multiple ports.
Difference between Reverse Proxy and Port Forwarding
While both methods might look similar, they are entirely different technically.
A proxy accepts a socket connection and fulfills the client request in some way or other. Usually, it creates its own request to the indicated server.
The by far most common example is an HTTP proxy that accepts HTTP requests from clients, uses its own HTTP request to retrieve the page/object, and then forwards the data to the client. Proxies can even translate application layer protocols (e. g. FTP over HTTP proxy) but they are always application-specific which makes them application-aware as well. Proxies were widely used for private-to-public Internet access before NAT become common. They can also be used for caching or deeper insight into the application protocol (application-layer gateway, malware scan, content filtering,… ).
A reverse proxy is used the other way around: public access for servers within private LANs. Since a proxy understands the application protocol, it can be used as a single entry point for multiple exposed servers, especially with HTTP. A reverse proxy can have multiple functions, including
caching
load balance across a number of backing servers
port sharing (multiple web servers are accessed using the same public IP address and transport-layer port number, distinguished by host header)
offloading SSL to the proxy
application-layer gateway/filtering
Port forwarding is another term for destination NAT aka reverse NAT, sometimes also virtual IP: a router translates a packet’s public destination address to the actual private address to enable access from the Internet to privately addressed servers. In contrast to a proxy, a NAT router is not aware of the application protocol that’s currently used. It only translates IP addresses and possibly transport-layer (L4) port numbers.
That way, it isn’t possible to enable public access to multiple private servers using a single public IP address and L4 port – you need to either have multiple public addresses or use multiple ports.
Frequently Asked Questions about reverse proxy port forwarding
Is it port forwarding the same as reverse proxy?
Port forwarding describes a layer-4 mechanism, operating on TCP connections or UDP packets without necessarily understanding the application data. Reverse proxy suggests a higher-layer (this is where the OSI model doesn’t map directly to TCP/IP) application-aware proxy.
Can you port forward with a proxy?
When a port forward is implemented by a proxy process (such as on application layer firewalls, SOCKS based firewalls, or via TCP circuit proxies), then no packets are actually translated, only data is proxied. This usually results in the source address (and port number) being changed to that of the proxy machine.
What is reverse and forward proxy?
A traditional forward proxy server allows multiple clients to route traffic to an external network. … A reverse proxy, on the other hand, routes traffic on behalf of multiple servers. A reverse proxy effectively serves as a gateway between clients, users, and application servers.Mar 31, 2021