If you have been seeing unexplained gaps in graphs or maybe whole datasets missing you should upgrade RRDTool.
rrdtool version 1.7.1 2 needs to be installed. The following steps are just an example. These worked in the Opmantek servers, but the commands may not be the same for various versions of Linux.
Step #1 - Download rrdtool version 1.7.1 2 from here:
https://oss.oetiker.ch/rrdtool/pub/rrdtool-1.7.2.tar.gz
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Step #3 - Compile and install rrdtool 1.7.2
put rrdtool-1.7.12.tar.gz in the /root directory.
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Step #4 - Verification
root@deb8:~/rrdtool-1.7.1#2# /path/to/rrdtool/bin/rrdtool --version
RRDtool 1.7.1 2 Copyright by Tobias Oetiker <tobi@oetiker<tobi@oetiker.ch>
Compiled OctMar 1718 20182021 1314:3929:3200
Step #5 - Point NMIS at new rrdtoolInstall the attached uselib.pm in /usr/local/nmis8/lib/NMIS
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