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ivan
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Message 34873 - Posted: 5 Apr 2018, 9:44:31 UTC

There was a major network problem at CERN this morning. It has apparently been resolved but not yet understood, according to the above link.
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computezrmle

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Message 34874 - Posted: 5 Apr 2018, 10:00:46 UTC - in response to Message 34873.  

CMS requests lots of data from cmsfrontier.cern.ch, usually via TCP port 8000.
Since the outage at CERN this morning my running VMs partly generate requests to cmsfrontier.cern.ch TCP port 80 instead.

A check shows that port 8000 responds as expected but not port 80.

nc -v -z -w 5 cmsfrontier.cern.ch 8000
Connection to cmsfrontier.cern.ch 8000 port [tcp/irdmi] succeeded!

nc -v -z -w 5 cmsfrontier.cern.ch 80
nc: connect to cmsfrontier.cern.ch port 80 (tcp) timed out: Operation now in progress

It should also be checked why the VMs generate wrong requests.
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ivan
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Message 34877 - Posted: 5 Apr 2018, 10:35:33 UTC - in response to Message 34874.  

That's working for me now:
[eesridr@pion:BOINC] > nc -v -z -w 5 cmsfrontier.cern.ch 8000
Connection to cmsfrontier.cern.ch 8000 port [tcp/irdmi] succeeded!
[eesridr@pion:BOINC] > nc -v -z -w 5 cmsfrontier.cern.ch 80
Connection to cmsfrontier.cern.ch 80 port [tcp/http] succeeded!

Thanks for the report, I guess it's up to CERN to look at the VM operation.
BTW, the outage affected our WMAgent too, but that was quickly rectified.
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Message 34878 - Posted: 5 Apr 2018, 12:59:20 UTC - in response to Message 34877.  

Although my project tasks are back to normal operation I wonder if there is an access restriction to port 80 for connections coming from outside.

I suspect this because the test is still not working:
nc -v -z -w 5 cmsfrontier.cern.ch 80
nc: connect to cmsfrontier.cern.ch port 80 (tcp) timed out: Operation now in progress


I crosschecked my firewall to see if there is a restriction, but all of my relevant local hosts are allowed to send/receive packets to/from CERN port 80.
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ivan
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Message 34879 - Posted: 5 Apr 2018, 13:29:48 UTC - in response to Message 34878.  

My connection was from London, so not inside the CERN network.
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