
Ask HN: Linux networking interview questions - thickice
What are some good interview questions for a kernel developer in the networking area (bridging, Layer2, netfilter&#x2F;iptables, IP routing, Layer 3 and TCP&#x2F;UDP stack)
======
hacknat
Give the lifecycle of an sk_buff structure from birth (in the driver) all the
way up to a user's socket read syscall. Familiarity with various layers and
how the TCP state machine works are a given. Do they know any dark corners? IP
routing in linux can do some incredible things, do they know anything about
that.

Sources:

[http://vger.kernel.org/~davem/skb.html](http://vger.kernel.org/~davem/skb.html)

[https://people.cs.clemson.edu/~westall/853/notes/skbuff.pdf](https://people.cs.clemson.edu/~westall/853/notes/skbuff.pdf)

If you're good enough to read the kernel code yourself take a look at a wifi
or ethernet driver with them and have them explain what's going on all the way
up the stack. Even if you don't know that much you'll be able to smell BS if
they don't.

~~~
thickice
thanks!

