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<p>Not necessarily. If the cluster is on a private network, some
node that connects to the public network needs to be configured to
act as a NAT gateway to forward traffic meant for the outside
world. This doesn't happen automatically. Some cluster admins
intentionally don't do this for security and bandwidth issues.
Other times it's merely an act of omission. <br>
</p>
<p>Allow access *out* to the internet doesn't allow bitcoin mining
and such. Allowing traffic from the outside *in* to the cluster is
what causes that kind of shenanigans. <br>
</p>
<p>Prentice<br>
</p>
<div class="moz-cite-prefix">On 8/2/20 5:13 PM, Brian Andrus wrote:<br>
</div>
<blockquote type="cite"
cite="mid:485a5d73-5da2-899a-e42f-b91d99f9e37c@gmail.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<p>This is very likely by design of the cluster and/or network.
Otherwise users could use the cluster to mine bitcoin and such.</p>
<p>Brian Andrus<br>
</p>
<div class="moz-cite-prefix">On 8/2/2020 7:11 AM, Mahmood Naderan
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CADa2P2WR3gePrVzPmx9Yhpm6zR+om=qUTZQ3Q+49-JpfarewLw@mail.gmail.com">
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charset=UTF-8">
<div dir="ltr">
<div class="gmail_default"
style="font-family:tahoma,sans-serif">I thought that maybe
srun doesn't transfer all settings from the head node to the
compute node.</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">The wget command works
on frontend but doesn't work on the compute.</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"> mahmood@main-proxy:~$
wget <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a><br>
--2020-08-02 16:05:55-- <a href="http://google.com/"
target="_blank" moz-do-not-send="true">http://google.com/</a><br>
Resolving <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> (<a
href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a>)... 216.58.215.238,
2a00:1450:400a:800::200e<br>
Connecting to <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> (<a
href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a>)|216.58.215.238|:80...
connected.<br>
HTTP request sent, awaiting response... 301 Moved
Permanently<br>
Location: <a href="http://www.google.com/" target="_blank"
moz-do-not-send="true">http://www.google.com/</a>
[following]<br>
--2020-08-02 16:05:55-- <a href="http://www.google.com/"
target="_blank" moz-do-not-send="true">http://www.google.com/</a><br>
Resolving <a href="http://www.google.com" target="_blank"
moz-do-not-send="true">www.google.com</a> (<a
href="http://www.google.com" target="_blank"
moz-do-not-send="true">www.google.com</a>)...
172.217.168.68, 2a00:1450:400a:803::2004<br>
Connecting to <a href="http://www.google.com"
target="_blank" moz-do-not-send="true">www.google.com</a>
(<a href="http://www.google.com" target="_blank"
moz-do-not-send="true">www.google.com</a>)|172.217.168.68|:80...
connected.<br>
HTTP request sent, awaiting response... 200 OK<br>
Length: unspecified [text/html]<br>
Saving to: ‘index.html’<br>
<br>
index.html [ <=>
] 12.68K --.-KB/s in 0s<br>
<br>
2020-08-02 16:05:56 (196 MB/s) - ‘index.html’ saved [12983]<br>
<br>
mahmood@main-proxy:~$ srun -p gpu_part --gres=gpu:titanv:1
--pty /bin/bash<br>
mahmood@fry0:~$ wget <a href="http://google.com"
target="_blank" moz-do-not-send="true">google.com</a><br>
--2020-08-02 16:05:30-- <a href="http://google.com/"
target="_blank" moz-do-not-send="true">http://google.com/</a><br>
Resolving <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> (<a
href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a>)... 216.58.215.238,
2a00:1450:400a:800::200e<br>
Connecting to <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> (<a
href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a>)|216.58.215.238|:80...
^C<br>
mahmood@fry0:~$<br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">I will check the
gateway with the admin. </div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif">Thanks for the hint.</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div class="gmail_default"
style="font-family:tahoma,sans-serif"><br>
</div>
<div>
<div dir="ltr" data-smartmail="gmail_signature">
<div dir="ltr"><font face="tahoma,sans-serif">Regards,<br>
Mahmood</font><br>
<br>
<br>
</div>
</div>
</div>
<br>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Sun, Aug 2, 2020 at 5:58
PM Renfro, Michael <<a href="mailto:Renfro@tntech.edu"
target="_blank" moz-do-not-send="true">Renfro@tntech.edu</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div>
<div dir="ltr">
<div> </div>
<div>
<div>
<div style="direction:ltr">Probably unrelated to
slurm entirely, and most likely has to do with
lower-level network diagnostics. I can guarantee
that it’s possible to access Internet resources
from a compute node. Notes and things to check:</div>
<div><br>
</div>
<div style="direction:ltr">1. Both ping and
http/https are IP protocols, but are very
different (ping isn’t even TCP or UDP, it’s ICMP),
so even if you needed proxy variables for http and
https to work, they shouldn’t affect ping.</div>
<div><br>
</div>
<div style="direction:ltr">2. Do http or https
transfers work from a compute node? A github
clone, a test with curl or wget to a nearby web
server? Do your proxy variables exist on the
compute node, and most importantly, is there a
proxy server listening and functional on the host
and port that the variables point to?</div>
<div><br>
</div>
<div style="direction:ltr">3. What’s the default
gateway for your compute nodes? Does that gateway
provide network address translation (NAT) for the
nodes, or does it work as a traditional router?</div>
</div>
<div><br>
</div>
<div>Get <a href="https://aka.ms/o0ukef"
target="_blank" moz-do-not-send="true">Outlook for
iOS</a></div>
</div>
<hr style="display:inline-block;width:98%">
<div
id="gmail-m_-3352875155037592075gmail-m_-6726695868362249448divRplyFwdMsg"
dir="ltr"><font style="font-size:11pt" face="Calibri,
sans-serif" color="#000000"><b>From:</b> slurm-users
<<a
href="mailto:slurm-users-bounces@lists.schedmd.com"
target="_blank" moz-do-not-send="true">slurm-users-bounces@lists.schedmd.com</a>>
on behalf of Mahmood Naderan <<a
href="mailto:mahmood.nt@gmail.com" target="_blank"
moz-do-not-send="true">mahmood.nt@gmail.com</a>><br>
<b>Sent:</b> Sunday, August 2, 2020 7:52:52 AM<br>
<b>To:</b> Slurm User Community List <<a
href="mailto:slurm-users@lists.schedmd.com"
target="_blank" moz-do-not-send="true">slurm-users@lists.schedmd.com</a>><br>
<b>Subject:</b> [slurm-users] Internet connection
loss with srun to a node</font>
<div> <span
style="font-family:tahoma,sans-serif;font-size:inherit;text-align:center">Hi</span></div>
</div>
<div>
<div>
<div dir="ltr">
<div style="font-family:tahoma,sans-serif">A
frontend machine is connected to the internet
and from that machine, I use srun to get a bash
on another node. But it seems that the node is
unable to access the internet. The http_proxy
and https_proxy are defined in ~/.bashrc</div>
<div style="font-family:tahoma,sans-serif"><br>
</div>
<div style="font-family:tahoma,sans-serif">mahmood@main-proxy:~$
ping <a href="http://google.com"
target="_blank" moz-do-not-send="true">google.com</a><br>
PING <a href="http://google.com"
target="_blank" moz-do-not-send="true">google.com</a>
(216.58.215.238) 56(84) bytes of data.<br>
64 bytes from <a
href="http://zrh11s02-in-f14.1e100.net"
target="_blank" moz-do-not-send="true">zrh11s02-in-f14.1e100.net</a>
(216.58.215.238): icmp_seq=1 ttl=114 time=1.38
ms<br>
^C<br>
--- <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> ping
statistics ---<br>
1 packets transmitted, 1 received, 0% packet
loss, time 0ms<br>
rtt min/avg/max/mdev = 1.384/1.384/1.384/0.000
ms<br>
</div>
<div style="font-family:tahoma,sans-serif">mahmood@main-proxy:~$ <span
style="font-family:Arial,Helvetica,sans-serif">srun
-p gpu_part --gres=gpu:titanv:1 --pty
/bin/bash</span></div>
<span style="font-family:tahoma,sans-serif"></span>mahmood
@fry0:~$ ping <a href="http://google.com"
target="_blank" moz-do-not-send="true">google.com</a><br>
PING <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a>
(216.58.215.238) 56(84) bytes of data.<br>
^C<br>
--- <a href="http://google.com" target="_blank"
moz-do-not-send="true">google.com</a> ping
statistics ---<br>
3 packets transmitted, 0 received, 100% packet
loss, time 2026ms<br>
<br>
<br>
<br>
<div style="font-family:tahoma,sans-serif">I guess
that is related to slurm and srun.</div>
<div style="font-family:tahoma,sans-serif">Any
idea for that?</div>
<br>
<br>
<div style="font-family:tahoma,sans-serif"> <br>
</div>
<div style="font-family:tahoma,sans-serif"><br>
</div>
<div style="font-family:tahoma,sans-serif"><br>
</div>
<div style="font-family:tahoma,sans-serif"><br>
</div>
<div style="font-family:tahoma,sans-serif"><br>
</div>
<div>
<div dir="ltr">
<div dir="ltr"><font face="tahoma,sans-serif">Regards,<br>
Mahmood</font><br>
<br>
<br>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
</div>
</blockquote>
</blockquote>
<pre class="moz-signature" cols="72">--
Prentice Bisbal
Lead Software Engineer
Research Computing
Princeton Plasma Physics Laboratory
<a class="moz-txt-link-freetext" href="http://www.pppl.gov">http://www.pppl.gov</a></pre>
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