48 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
[[!meta title="Tunneling the qemu or kvm vnc unix socket via ssh"]]
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Perhaps you were searching for a way to tunnel the
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[unix socket](http://en.wikipedia.org/wiki/Unix_domain_socket)
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provided by
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[qemu](http://www.qemu.org/)
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or [kvm](http://www.linux-kvm.org/page/Main_Page)
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for [vnc](http://en.wikipedia.org/wiki/Virtual_Network_Computing)
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through an [ssh](http://www.openssh.com/) tunnel, too?
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When I was searching for an answer, I found 
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[ssvnc](http://www.karlrunge.com/x11vnc/ssvnc.html), which
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I did not give a try, because I wanted to solve the problem
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with [socat](http://www.dest-unreach.org/socat/) and ssh.
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I started kvm on the **remote** machine using the following command:
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    kvm -vnc unix:/home/services/vms/vnc-socket ...
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Then I connected socat locally on the remote machine to test the settings:
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    socat STDIO UNIX-CONNECT:/home/services/vms/vnc-socket
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Which worked pretty fine. On the local side we need a listener on a
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tcp port around port 5500+ (not a must, but the standard vnc port), which
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can be created like that:
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    socat STDIO TCP-LISTEN:5500
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As reading and writing is not possible with a single pipe, one **cannot** just do
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pipe into socat like this:
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    ssh root@tee.schottelius.org "socat STDIO UNIX-CONNECT:/home/services/vms/vnc-socket" | socat STDIO TCP-LISTEN:5500
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But socat has another nice option, the **EXEC** parameter, which solves the problem:
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    socat TCP-LISTEN:5500 EXEC:'ssh root@tee.schottelius.org "socat STDIO UNIX-CONNECT:/home/services/vms/vnc-socket"'
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And now I can connect locally via [tightvnc](http://www.tightvnc.com/):
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    xtightvncviewer -encodings "copyrect tight hextile zlib corre rre raw" localhost:5500
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I specify a different order for the encodings, because xtightvncviewer
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prefers raw "encoding", if it connects to localhost, which is not desired
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here.
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And that's it, vnc connected to a unix socket from kvm tunneled through ssh!
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[[!tag unix vm]]
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