File replication across a WAN - can't get it to work

[To-M]

http://www.liutilities.com/tcp-udp-port/873/

The rsync application essentially uses the port 873. This application can only be found on computers that are running on the UNIX OS. Rsync is utilized in the synchronization of folders and files in computers, even when the machines are not connected or physically close to each other. This information is transferred through the Local Access Network or the LAN or the Internet. The application associated with the port runs a background process and also listens to the port 873 on the TCP protocol. This information that is passing through this port 873 flows to and fro the computer.

http://ss64.com/bash/rsync.html

In this case you will connect to a remote rsync server running on TCP port 873.
You may establish the connection via a web proxy by setting the environment variable RSYNC_PROXY to a hostnameort pair pointing to your web proxy.
Note that your web proxy's configuration must allow proxying to port 873.
Using rsync in this way is the same as using it with rsh or ssh except that:


http://www.auditmypc.com/tcp-port-873.asp
PORT 873 – Information

• Port Number: 873
• TCP / UDP: TCP
• Delivery: Yes
• Protocol / Name: rsync
• Port Description: rsync.’rsync’
• TCP Port 873 may use a defined protocol to communicate depending on the application. A protocol is a set of formalized rules that explains how data is communicated over a network. Think of it as the language spoken between computers to help them communicate more efficiently.
• TCP port 873 uses the Transmission Control Protocol. TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered on port 873 in the same order in which they were sent. Guaranteed communication over port 873 is the key difference between TCP and UDP. UDP port 873 would not have guaranteed communication in the same way as TCP.

http://www.open-e.com/site_media/dow...April_2009.pdf

There is so much more about this when you google about rsync and port 873. Ok time for me to go now see everyone next week!

[Gr-R]

removed for double post

[Gr-R]

Any other explanation, please contact me directly! This is fairly to the point, and understand we use rsync as open source, nothing special here!

http://www.liutilities.com/tcp-udp-port/873/

The rsync application essentially uses the port 873. This application can only be found on computers that are running on the UNIX OS. Rsync is utilized in the synchronization of folders and files in computers, even when the machines are not connected or physically close to each other. This information is transferred through the Local Access Network or the LAN or the Internet. The application associated with the port runs a background process and also listens to the port 873 on the TCP protocol. This information that is passing through this port 873 flows to and fro the computer.

http://ss64.com/bash/rsync.html

In this case you will connect to a remote rsync server running on TCP port 873.
You may establish the connection via a web proxy by setting the environment variable RSYNC_PROXY to a hostnameort pair pointing to your web proxy.
Note that your web proxy's configuration must allow proxying to port 873.
Using rsync in this way is the same as using it with rsh or ssh except that:


http://www.auditmypc.com/tcp-port-873.asp
PORT 873 – Information

• Port Number: 873
• TCP / UDP: TCP
• Delivery: Yes
• Protocol / Name: rsync
• Port Description: rsync.’rsync’
• TCP Port 873 may use a defined protocol to communicate depending on the application. A protocol is a set of formalized rules that explains how data is communicated over a network. Think of it as the language spoken between computers to help them communicate more efficiently.
• TCP port 873 uses the Transmission Control Protocol. TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered on port 873 in the same order in which they were sent. Guaranteed communication over port 873 is the key difference between TCP and UDP. UDP port 873 would not have guaranteed communication in the same way as TCP.

http://www.open-e.com/site_media/dow...April_2009.pdf

There is so much more about this when you google about rsync and port 873. Ok time for me to go now see everyone next week!

[msutherland25]

I never suggested that tcp/873 was not used by rsync! I know that it is used by rsync, but my original question was asking how to allow a DSS on an internal network to replicate to an external DSS on a public IP. In this scenario, allowing tcp/873 has nothing to do with it since in the vast majority of cases, most types of trafiic are allowed out from a internal server. The solution was allowing icmp packets from outside and mapping them back to the internal DSS address which is something your documentation mentions nothing about. It seems that your documentation covers the reverse situation only. I sincerely hope this thread helps someone else out there and I really don't want to upset anyone, but this whole business should not have been such hard work!

[msutherland25]

Further to the above, I have used rsync for years to keep a copies of files on rsync servers hosted in data centres without needing any special firewall changes. The issue relates to some kind of check that DSS is doing prior to starting the sync!