It's week 07 of my #SysAdmin class, high time we talk about the cause of (and solution to) all problems: the #DNS.
We look at the history of the DNS and how we used to copy giant hosts file around, trace DNS packets from resolvers to the root servers and the various authoritative NS using our good friend #tcpdump, talk about #TLDs, fetch the root zone from InterNIC to bootstrap our resolver, look at different RRs, reverse lookups, and touch upon #dnssec.