First try.

Use Ubuntu Xenial as it will be supported for about 1.5 years from now.

.dockerignore

+*

.gitignore

+~*
+*~
+*.sw[op]
+*.py[cod]
+.DS_Store
+__pycache__/
+.vagrant/
+vendor/
+Thumbs.db
+*.retry
+.svn/
+.sass-cache/
+*.log
+*.out
+*.so
+node_modules/
+.npm/
+nbproject/
+*.ipynb
+.idea/
+*.egg-info/
+*.[ao]
+.classpath
+.cache/
+bower_components/
+*.class
+*.[ewj]ar
+secring.*
+.*.kate-swp
+.swp.*
+.directory
+.Trash-*
+build/
+_build/
+dist/
+.tox/
+*.pdf
+*.exe
+*.dll
+*.gz
+*.tgz
+*.tar
+*.rar
+*.zip
+*.pid
+*.lock
+*.env
+.bundle/
+!Pipfile.lock

Dockerfile

+FROM ubuntu:xenial
+RUN apt-get update && \
+    apt-get install -y nagios-nrpe-plugin && \
+    rm -rf /tmp/* /var/tmp/* /var/lib/apt/lists/* /var/cache/apt/archives/*
+USER nobody
+ENV PATH=/usr/lib/nagios/plugins:/usr/local/bin:/usr/bin:/bin
+ENTRYPOINT ["check_nrpe"]
+RUN check_nrpe --help

LICENSE.txt

+MIT License
+
+Copyright (c) 2019 Adar Nimrod
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

+# check_nrpe
+
+A version 2 `check_nrpe` for cases when the OS only has packages for version 3.
+
+## Usage
+
+`docker run adarnimrod/check_nrpe -h foo.example.com`
+
+## License
+
+This software is licensed under the MIT license (see `LICENSE.txt`).
+
+## Author Information
+
+Nimrod Adar, [contact me](mailto:nimrod@shore.co.il) or visit my [website](
+https://www.shore.co.il/). Patches are welcome via [`git send-email`](
+http://git-scm.com/book/en/v2/Git-Commands-Email). The repository is located
+at: <https://www.shore.co.il/git/>.