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Examining DNS - Quiz

Each question is worth one point. Select the best answer or answers for each question.

1.	Which command-line tool is the current standard for interactively querying and debugging DNS on Linux and BSD systems? Please select the correct answer:
	A.	`nslookup`
	B.	`dig`
	C.	`ping`
	D.	`traceroute`

2.	On a typical systemd-based Linux host, `/etc/resolv.conf` contains the single entry `nameserver 127.0.0.53`. What does this indicate? Please select the correct answer:
	A.	The host is misconfigured and has no working name server
	B.	The host is running an authoritative name server for its own zone
	C.	Queries are being sent to the local `systemd-resolved` stub listener, which forwards to the real upstream servers
	D.	The host resolves all names from `/etc/hosts` only

3.	Besides the `named` daemon itself, which of the following are components of a working BIND 9 installation? Please select all the correct answers:
	A.	The `named.conf` configuration file
	B.	The `/etc/hosts` static host table
	C.	The zone data files referenced by `named.conf`
	D.	The `rndc` control utility and its `rndc.key` shared secret

4.	What is the function of the `directory` statement inside the `options` block of `named.conf`? Please select the correct answer:
	A.	To declare the server authoritative for a zone
	B.	To set the working directory that relative file paths elsewhere in the configuration are resolved against
	C.	To specify the location of the DNSSEC trust anchors
	D.	To restrict which clients may send recursive queries

5.	A BIND 9 resolver defines a zone of `type hint` pointing at a file such as `named.ca` or `db.root`. What is that file for? Please select the correct answer:
	A.	To serve as the zone file for the loopback address
	B.	To hold the DNSSEC signing keys for locally hosted zones
	C.	To prime the resolver with the names and addresses of the root name servers
	D.	To cache answers persistently across restarts of `named`

6.	Which command directs a query to the specific name server at `192.0.2.53` rather than the system default resolver? Please select the correct answer:
	A.	`dig @192.0.2.53 example.com`
	B.	`dig --server=192.0.2.53 example.com`
	C.	`dig example.com 192.0.2.53`
	D.	`dig -s 192.0.2.53 example.com`

7.	You need to inspect the SOA record for `example.com`. Why is `dig ANY example.com` an unreliable way to do this in the current environment? Please select the correct answer:
	A.	The `ANY` query type was removed from the DNS protocol
	B.	Under RFC 8482, servers commonly return a minimal or synthetic response to `ANY` instead of the full record set, so the query type must be requested explicitly
	C.	`dig` does not support the SOA record type
	D.	SOA records may only be retrieved by the zone primary