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I am having an odd issue wherein suddenly port forwarding stopped working in a particular scenario for me. By default I need a particular port forwarded on all servers I manage and so I have the following in my ~/.ssh/config file:

Host *
    ControlMaster auto
    ControlPath /tmp/%r@%h:%p
    ServerAliveInterval 120
    ServerAliveCountMax 3

    ForwardX11 yes
    ForwardX11Trusted yes

    RemoteForward 52698 127.0.0.1:52698

I then initiate ssh to the server (ssh username@server.tld) and query my local workstation to make sure that there are listeners for port 52698; sudo lsof -i -P | grep 52698:

AppName   40262        username   45u  IPv6 0x4b497d2de68055a1      0t0    TCP *:52698 (LISTEN)
sshd      92207        username   14u  IPv6 0x4b497d2d9e7ec4a1      0t0    TCP localhost:52698 (LISTEN)
sshd      92207        username   15u  IPv4 0x4b497d2dbb985641      0t0    TCP localhost:52698 (LISTEN)

I then likewise make sure that the port is active on the server, lsof -P | grep 52698:

sshd      16366      root    7u     IPv6             196798        0t0        TCP localhost:52698 (LISTEN)
sshd      16366      root    8u     IPv4             196799        0t0        TCP localhost:52698 (LISTEN)

I am not sure what may have provoked this to stop working. I have tried several Internet connections from various ISPs and VPNs to no avail in terms of getting past this, so I have to assume that this is a local issue to my workstation and the connection to the server, but I'm not seeing a solution or exactly where to look in order to find out what might be going on here. Any ideas?

share|improve this question
    
What is the problem you are having? –  Michael Hampton Dec 30 '13 at 1:31
    
On the remote server the application that tunnels data back to my workstation is not working. It is a ruby script that is simply failing to use the tunnel to get the information over when I specify a port. –  ylluminate Dec 30 '13 at 1:40
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