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Sean,<br>
<br>
Undocumented feature, I'm afraid...sorry...<br>
<br>
There really are two servers. Outside the lab, hallddb.jlab.org
resolves to a server that, as you can tell, is accessible via mysql
on the standard port. Inside the lab, hallddb.jlab.org resolves to
halldweb1.jlab.org (one node, runs both webserver and db server).
The outward facing server gets updated nightly, but is read-only,
enforced via the native mysql access control. That way anyone can
see our calibration constants but no one can change them. The one
inside the lab is the "real" one, obviously.<br>
<br>
So we are protected only by the lab's standard login protection;
anyone that can log in to JLab can change the database. We record
all of the history in the database itself and have a backup scheme.
These gives us some protection against inadvertent changes coming
from JLab users, most likely GlueX collaborators. Note further that
if you use a time specification when requesting constants, you are
completely immune to changes.<br>
<br>
The update of the outward facing server happens at midnight, so
changes made on the inside are not instantly available on the
outside.<br>
<br>
The advantage is that the same CCDB_CONNECTION environment variable
works both inside and outside the lab, unless you want to write. The
disadvantage is that it is confusing to experts. It borders on being
a bit too clever, I admit.<br>
<br>
This may change as we re-arrange the servers in the near future. In
particular, we will almost certainly have an independent database
server on the inside.<br>
<br>
-- Mark<br>
<br>
<div class="moz-cite-prefix">On 05/15/2014 04:09 PM, Sean Dobbs
wrote:<br>
</div>
<blockquote
cite="mid:CAEAoKm5sy4+8ToS9s4w6J5b0Y_6LGr8ZJnZ062Ohapy5MMD8CA@mail.gmail.com"
type="cite">
<div dir="ltr">Hi Mark,
<div><br>
</div>
<div>I've been playing around the constants a bit today, and am
a bit confused about which server I should be accessing. This
came up since I noticed that on the CUE, when I try to look up
the location of <a moz-do-not-send="true"
href="http://hallddb.jlab.org">hallddb.jlab.org</a>, I get
this:</div>
<div><br>
</div>
<div>
<div>ifarm1101> host <a moz-do-not-send="true"
href="http://hallddb.jlab.org">hallddb.jlab.org</a></div>
<div><a moz-do-not-send="true" href="http://hallddb.jlab.org">hallddb.jlab.org</a>
is an alias for <a moz-do-not-send="true"
href="http://halldweb1.jlab.org">halldweb1.jlab.org</a>.</div>
<div><a moz-do-not-send="true"
href="http://halldweb1.jlab.org">halldweb1.jlab.org</a>
has address 129.57.64.28</div>
<div><br>
</div>
<div>But at NU, I get the following mapping:</div>
<div><br>
</div>
<div><a moz-do-not-send="true" href="http://hallddb.jlab.org">hallddb.jlab.org</a>
-> 129.57.52.40<br>
</div>
<div><a moz-do-not-send="true"
href="http://halldweb1.jlab.org">halldweb1.jlab.org</a>
-> 129.57.64.28<br>
</div>
<div><br>
</div>
<div>I remember that awhile back you moved some servers
around, so I'm not sure if this is a DNS problem or not.
Can you remind me which is the right place to access?
(side note: I can get at the CCDB in 129.57.64.28 just fine
on the ifarm, but not from NU).</div>
<div><br>
</div>
<div><br>
</div>
<div>Cheers,</div>
<div>Sean</div>
<div>
<div><br>
</div>
-- <br>
<div dir="ltr">Sean Dobbs<br>
Department of Physics & Astronomy <br>
Northwestern University<br>
phone: 847-467-2826</div>
</div>
</div>
</div>
</blockquote>
<br>
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