In the example below what do the channel numbers correspond to? Which are on the server? Which are on the client?
$ ssh -L1570:127.0.0.1:8899 root@thehost
Password:
Last login: Fri Aug 9 13:08:44 2013 from theclientip
Sun Microsystems Inc. SunOS 5.10 Generic January 2005
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# channel 2: open failed: administratively prohibited: open failed
channel 3: open failed: administratively prohibited: open failed
channel 2: open failed: administratively prohibited: open failed
The ssh client is running on Windows 7 and the server has a Tomcat server running on port 8899.
Tomcat is not listening on 127.0.0.1 on the remote machine so if I change the command to ssh -L1570:thehostpublicip:8899 root@thehost
the port forward works. So I know that port forwarding seems to be working just fine on the server.
my sshd config file contains the following two lines:
# Port forwarding
AllowTcpForwarding yes
# If port forwarding is enabled, specify if the server can bind to INADDR_ANY.
# This allows the local port forwarding to work when connections are received
# from any remote host.
GatewayPorts yes
I'm trying to setup port forwarding for another process not Tomcat and I get the error messages similar to the stuff above so I'm trying to understand the meaning of the error messages.
Best Answer
From the SSH Protocol documentation, regarding channels:
Port forwarding
The command you have looks fine. Are you sure that the service you're trying to connect to is up and accepting connections? The channel errors would seem to indicate that it's not.
What are my active channels?
If you have an active
ssh
connection you can use the following key combination to get help:Shift+~ followed by Shift+?
You can then use this key combination to get a list of the active channels:
Shift+~ followed by Shift+#