<div class="gmail_quote"><div>I had exactly this problem, even though scp seemed to work fine. I gave up in the end and just turned off checking<br><br>$rcpcmd /usr/bin/scp -o StrictHostKeyChecking=no<br><br>problem went away. <br>
<br>I have been dealing with a much more evil problem doing some benchmarking though. I run 100 jobs on a cluster of 4 core machines (so load could be up to 4 per node). If I run say jobs with a very short duration e.g 0.1 seconds, the stdout and stderr are copied back only partially. In some tests as few as 80 out of 100 arrived successfully . T he missing files were left on the nodes themselves. If I tried jobs with slightly longer duration (e.g 5 seconds), it did better but<br>
still only 95% returned. I assume the problem is some kind of denial of service due to many jobs exitting synchronously but since I can't assume things will exit nicely spaced out in production, this seems to be a concern. I also did some stress testing of the cluster, killing and resarting the mom processes to simulate node failure and saw a low but significant rate where the same job ran twice on a node (once unsuccessfully and once sucessfully) and the stdout was concatenated giving me two copies of the desired output. Also not good for a production system. Any advice or is using scp fundamentally a bad idea?<br>
<br>Darren<br>\<br>
</div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div><br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
You might make sure you can ssh a few ways back and forth to set the ssh keys. I noticed I would ssh to the short hostname all the time and would get stung by this since I hadn't ssh'd to the machine with the full hostname too. Just a thought.<br>
<br>
-Steve<br>
<br>
On Jun 5, 2008, at 12:03 PM, Adrian Sevcenco wrote:<br>
<br>
</blockquote>
<br></div>
I continue to be a bit confused on this topic, is passwordless ssh required both ways for root, the user or, both?<br><font color="#888888">
<br>
Tony Schreiner<br>
Boston College</font><div><div></div><div><br>
_______________________________________________<br>
torqueusers mailing list<br>
<a href="mailto:torqueusers@supercluster.org" target="_blank">torqueusers@supercluster.org</a><br>
<a href="http://www.supercluster.org/mailman/listinfo/torqueusers" target="_blank">http://www.supercluster.org/mailman/listinfo/torqueusers</a><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br>Darren Platt<br>Senior Director, Research<br>23andMe, inc