mathlink error when restarting remote kernel
- To: mathgroup at smc.vnet.net
- Subject: [mg68141] mathlink error when restarting remote kernel
- From: Ryan Olf <ryanolf at gmail.com>
- Date: Tue, 25 Jul 2006 04:01:53 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I use my Mac OS X Mathematica 5.2 (for students) frontend to connect to a remote kernel (version 5.2 for Linux) over SSH. The commands I use, and work pretty well, are: Arguments to MLOpen: -LinkMode Listen -LinkProtocol TCPIP -LinkName 31416 at 127.0.0.1,31417 at 127.0.0.1 -LinkOptions MLDontInteract Launch Command: ssh -R 31416:127.0.0.1:31416 -R 31417:127.0.0.1:31417 remotehost "/ usr/local/bin/math -mathlink -LinkMode Connect -LinkProtocol TCPIP - LinkName 31416 at 127.0.0.1,31417 at 127.0.0.1 -LinkHost 127.0.0.1" The remote machine is behind a firewall, so the mathlink connection is tunneled through SSH. With these commands I can start the remote kernel, execute commands through the front end, everything is fine and dandy. Until I try to quit the kernel. If I quit the kernel by executing the "Quit" command, the kernel exits cleanly, and I can start it back up again instantly. Excellent. If, however, I quit the kernel via the frontend menus Kernel->Quit Kernel->remote kernel, the kernel exits cleanly, but when I try to restart the kernel, I get an error message: Mathematica could not establish a connection to the kernel. Kernel: remote kernel. Low-level MathLink error: The linkname is already in use. Checking on the remote computer, there is no kernel running, as expected. It does seem to be shut down properly. If I wait a few minutes after quitting the kernel using the menus, I do not get the error message, and I'm on my merry way. I think the issue has to do with MLOpen (whatever that is). For some reason, when I quit the kernel using the Quit command, MLOpen stops listening to the linkname and a link can be set up again immediately. When I quit using the menus, MLOpen takes a few minutes to stop listening to the linkname. My question for the experts out there is: how do I fix this issue? Is this a bug that Wolfram should know about and needs to fix? Or is there a problem in my configuration? Admittedly, this is not a critical issue, since everything is fine when I type "Quit" instead of using the menus, but nonetheless, I don't think the program should behave in this manner. Thank you in advance, Ryan
- Follow-Ups:
- Re: mathlink error when restarting remote kernel
- From: Steve Wilson <stevew@wolfram.com>
- Re: mathlink error when restarting remote kernel