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<p><font face="monospace">Hi,</font></p>
<p><font face="monospace">Thanks for the confirmation regarding the
FSD flag. <br>
</font></p>
<p><font face="monospace">I tried to use nut-ipmipsu for this, since
the PSUs were picked up by nut-scanner on my test server. But I
wasn't successful in configuring the driver correctly, or maybe
it's not yet compatible with my chassis at its current version.
I'll try to work on that in the next few days. If not I'll dive
in upssched to see if a solution lies there.<br>
</font></p>
<p><font face="monospace">Thanks</font></p>
<p><font face="monospace">Arthur Desplanches<br>
</font></p>
<div class="moz-cite-prefix"><font face="monospace">On 4/17/22
01:13, Jim Klimov wrote:<br>
</font></div>
<blockquote type="cite"
cite="mid:CAJYg8vJf+qSEmthDY1CmALRh2Soq_4Za9jSyCCXEx8-Kg5YehA@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="auto"><font face="monospace">As far as I know the FSD
flag by design can only be raised; many phrases refer to it as
"latching" - much for the same reasons as you outlined: people
usually want the datacenter in a predictable hands-off state.
If something begins to shut down due to critical power state
of the UPS, everything should power-cycle and come up together
and in order. So the only way to clear FSD is to restart the
daemons raising it.</font>
<div dir="auto"><font face="monospace"><br>
</font></div>
<div dir="auto"><font face="monospace">Note some UPSes and their
smart drivers would treat as critical any situation where
battery charge is under a certain threshold - even if online
and charging at the moment, since the UPS is too depleted
for a safe shutdown if power is lost again.</font></div>
<div dir="auto"><font face="monospace"><br>
</font></div>
<div dir="auto"><font face="monospace">I wonder if you can
fiddle with ipmi-psu driver for your case. NUT has a way to
treat blade chassis as an ePDU for the blades. Maybe you can
get upsmon to monitor an UPS and the other PSU on
redundant-PSU systems.</font></div>
<div dir="auto"><font face="monospace"><br>
</font></div>
<div dir="auto"><font face="monospace">Also see if some smarter
scripting with upssched (as the handler of signals from
upsmon for complex situations) can help...</font></div>
<div dir="auto"><font face="monospace"><br>
</font></div>
<div dir="auto"><font face="monospace">Hope this helps,</font></div>
<div dir="auto"><font face="monospace">Jim Klimov</font></div>
</div>
<font face="monospace"><br>
</font>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr"><font face="monospace">On Fri,
Apr 15, 2022, 14:17 Arthur Desplanches <<a
href="mailto:adesplanches@buf.com" moz-do-not-send="true"
class="moz-txt-link-freetext">adesplanches@buf.com</a>>
wrote:<br>
</font></div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"><font
face="monospace">Hi,<br>
</font>
<font face="monospace"><br>
I'm working on deploying NUT for our main server room, and
I've put <br>
myself in a situation where there could be an edge case that
I don't <br>
really like, and so I'm asking for a bit of guidance.<br>
</font>
<font face="monospace"><br>
Most of the deploymentis fairly standard according to the
documentation <br>
(big thanks for its exhaustiveness, by the way), the main
change is my <br>
shutdown script. It checks if we have power on both PSUs
using IPMI, and <br>
if this is the case, it doesn't shut down (in any other case
it does : <br>
ipmi doesn't work, only one PSU is receiving power, only one
PSU exists <br>
on the machine, etc). We did this because about 90% of our
machines have <br>
dual redundant PSUs, with one on the UPS, the other on mains
buton a <br>
separate circuit. So we could have a situation where the UPS
loses <br>
power, but we still have some on a secondary circuit.<br>
</font>
<font face="monospace"><br>
We choose to accept the fact that if the secondary circuit
loses power <br>
after our NUT server sent a force shutdown sequence, we may
have a bad <br>
shutdown at this point.<br>
</font>
<font face="monospace"><br>
What could happen in this situation, is that a machine that
is a <br>
nut-server (A) still has the FSD flag running (because it
didn't shut <br>
itself down) even after power comes back and some machines
restart. In <br>
this case, the upsmon on the freshly started machines will
see the flag <br>
and then shut themselves down again.<br>
</font>
<font face="monospace"><br>
Our workaround currently would be to be aware of this and
restart <br>
nut-server and then nut-monitor on the machine A before
starting back <br>
any of its clients that is currently down.<br>
</font>
<font face="monospace"><br>
Is there any idea of a better way to handle this edge case ?
Or a better <br>
way to articulate this ? Maybe a way to automatically clear
the FSD flag ?<br>
</font>
<font face="monospace"><br>
Thanks for the help<br>
Arthur<br>
</font>
<font face="monospace"><br>
-- <br>
Arthur Desplanches<br>
Sysadmin @ BUF Compagnie (<a href="http://buf.com"
rel="noreferrer noreferrer" target="_blank"
moz-do-not-send="true">buf.com</a>)<br>
</font>
<font face="monospace"><br>
</font>
<font face="monospace"><br>
_______________________________________________<br>
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</font>
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href="mailto:Nut-upsuser@alioth-lists.debian.net"
target="_blank" rel="noreferrer" moz-do-not-send="true"
class="moz-txt-link-freetext">Nut-upsuser@alioth-lists.debian.net</a><br>
</font>
<font face="monospace"><a
href="https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsuser"
rel="noreferrer noreferrer" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsuser</a><br>
</font>
</blockquote>
</div>
</blockquote>
<pre class="moz-signature" cols="72">--
Arthur Desplanches
Sysadmin</pre>
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