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<p>Folks,<br>
</p>
<p>The JLab Computer Center recently deployed some new farm nodes
running CentOS 7.7. See <a moz-do-not-send="true"
href="https://mailman.jlab.org/pipermail/jlab-scicomp-briefs/2019q4/000229.html">this
announcement</a> for some of the details.</p>
<p>Our pre-existing build at JLab on the older CentOS 7.2
distribution is not compatible with the new nodes. It should be,
but for a variety of reasons, it is not. See below for more on
this. For this reason, I have just done a complete, independent
build of our software stack on 7.7. There is also a new version of
build_scripts that sets a BMS_OSNAME that distinguishes between
the old CentOS 7 and the new CentOS 7. The new BMS_OSNAME is</p>
<p> Linux_CentOS7.7-x86_64-gcc4.8.5</p>
<p>This will be set automatically if you use Build Scripts to set-up
your environment. In that case no user action is necessary to use
the new nodes. Furthermore, this should have no impact on any
builds done outside of the JLab farm/ifarm cluster.<br>
</p>
<p>The main issue causing the conflict is a non-standard version of
MySQL on the 7.2 nodes. That version is built into many of our
binary executables and to make them run under 7.7 would require
the same non-standard MySQL install on the new nodes, which we do
not want. Better to have a complete build in the new, more
standard environment.</p>
<p>In addition Python is now coming from /usr/bin, not /apps/bin as
it was under 7.2, and Cmake3 is coming from /usr/bin and not
/apps/cmake/cmake-3.5.1/bin. This is also manifestly in the
direction of a more standard environment. If /apps/bin is in your
path on CentOS 7.7 on the ifarm at JLab, you might want to be
careful. <br>
</p>
<p> -- Mark</p>
<p><br>
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