Resolvconf
https://duckduckgo.com/?q=resolvconf&atb=v25&ia=qa
http://askubuntu.com/questions/130452/how-do-i-add-a-dns-server-via-resolv-conf#134106


Also this approach can be used:
/etc/network/interface
source /etc/network/interface.d/*

/etc/network/interface.d/eth1

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https://en.wikipedia.org/wiki/DMARC

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http://wicd.sourceforge.net/
https://github.com/uoaerg/wavemon