Network: SSH2: Hm, dispatch protocol error: type 20 plen 136

(last edit: 2001-04-06)

Problem

You have a good working ssh connection to a server and after a while happy typeing you get the following error: "Hm, dispatch protocol error: type 20 plen 136" and the connection hangs.

Solution

First of all: you can get your window back by typeing '~.' this will kill your ssh session. I searched for a solution to this problem and came accros an e-mail about this problem. This is what they said: "Anyway, the error is the same one OpenSSH gets when a rekey request comes in from the server. I discovered this when a client who uses OpenSSH (v2.3.0) was connecting to a server that got upgraded to ssh.com's v2.3.0. Seems the default for the ssh.com ssh2 server is to force a rekey every 1 hour. It was fixed when the server was reconfiged to not force a rekey (RekeyIntervalSeconds 0). Clients could still request it, but the server wouldn't force it. This is needed since OpenSSH and some other ssh clients don't support rekeys or support them improperly (info in ssh.com's ssh2d man page)." I came across some other postings which basicly said the same thing. So the problem can be solved on the server which runs sshd2. Edit the file /usr/local/etc/ssh2/sshd2_config and add the line 'RekeyIntervalSeconds 0'. Make sure that you can telnet to the server, Make a telnet connection, Kill the sshd2 deamon, Start the ssdh2 deamon. You can't just killall -HUP the deamon, that just won't work.

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