Although this post is nearly a year old, it is still gold. Ken Duda, the CTO of Arista Networks described five lessons learned along the way of supporting Enterprise Operating System (EOS), the Linux-based switching operating system. They are listed as:

1. It’s okay to leave the door unlocked.
2. Preserve the integrity of the Linux core.
3. Focus on state, not messages.
4. Keep your hands out of the kernel.
5. Provide familiar interfaces to ease adoption.

Definitely worth a read.