LHC@home

I re-enabled crunching here after a hiatus, and downloaded a large work unit, my first for some years. Big download, but it went okay. The work unit started running and went merrily on its way for just over a minute when it crashed out with a computation error. The reason puzzled me...

Exit status -203 (0xFFFFFF35) ERR_NO_NETWORK_CONNECTION

... about one minute after it had just downloaded the thing?

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Wave upon wave of demented avengers march cheerfully out of obscurity into the dream.

The only work units that are properly self-contained in LHC@home are part of the the SixTrack and the sixtracktest subprojects. The rest require a network connection to even run.

There is nothing wrong with my network connection, obviously, if it is some link to a required external resource that is missing, well, nothing I can do about that is there. My hiatus may resume.

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Wave upon wave of demented avengers march cheerfully out of obscurity into the dream.

I got yesterday also one of those. Below is a snipet from the log:

2017-01-03 14:02:56 (1848): Guest Log: [INFO] Shared directory mounted, enabling vboxmonitor
2017-01-03 14:02:56 (1848): Guest Log: [DEBUG] Testing network connection to cern.ch on port 80
2017-01-03 14:02:56 (1848): Guest Log: [DEBUG] nc: connect to cern.ch port 80 (tcp) timed out: Operation now in progress
2017-01-03 14:02:56 (1848): Guest Log: nc: connect to cern.ch port 80 (tcp) failed: Network is unreachable

The odd thing is that the timeout for the connection is less than a second according to the log. That kind of delay can always happen without any problem in the network connection.

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The timeout is 5 seconds, which should be sufficient, and it can easily be increased if this is an issue. If it really did return in less than one second then it suggests that there is indeed no network from the internal perspective of the VM. If temporary, then the subsequent task should work. If persistent then we have an issue that needs further investigation.

Well the host (laptop) is in wlan now so that adds more uncertainty level for the network connection. But anyhow it managed to report the failed task in less than two minutes after the log said the failure happened. Anyway it has finished two CMS tasks since so it was an intermittent failure.

A five second timeout is a bit short. To get the communication as robust as possible maybe a communication retry and a longer timeout is needed before giving up?

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Hi
what is this error code?
-1073740791 (0xC0000409) STATUS_STACK_BUFFER_OVERRUN
and how do I fix it?
Ross*

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this error is:

VM Heartbeat file specified, but missing file system status. (errno = '2')

There was an update to fix this plus the windows patches.