server:
	minimal-responses: no
	serve-expired: yes
	# The value does not matter, we will not simulate delay.
	# We do not want only serve-expired because fetches from that
	# apply a generous PREFETCH_LEEWAY.
	serve-expired-client-timeout: 1000
	# So that we can only have to give one SERVFAIL answer.
	outbound-msg-retry: 0

forward-zone: name: "." forward-addr: 216.0.0.1
CONFIG_END

SCENARIO_BEGIN RRset from cache updates the message TTL.

STEP 1 QUERY
ENTRY_BEGIN
	REPLY RD
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
; the query is sent to the forwarder - no cache yet.
STEP 2 CHECK_OUT_QUERY
ENTRY_BEGIN
	MATCH qname qtype opcode
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
STEP 3 REPLY
ENTRY_BEGIN
	MATCH opcode qtype qname
	ADJUST copy_id
	; authoritative answer
	REPLY QR AA RD RA NOERROR
	SECTION QUESTION
	www.example.com. IN A
	SECTION ANSWER
	www.example.com. 5 IN A 10.20.30.40
	SECTION AUTHORITY
	example.com. 10 IN NS ns.example.com.
	SECTION ADDITIONAL
	ns.example.com. 10 IN A 10.20.30.50
ENTRY_END
STEP 4 CHECK_ANSWER
ENTRY_BEGIN
	MATCH all ttl
	REPLY QR RD RA
	SECTION QUESTION
	www.example.com. IN A
	SECTION ANSWER
	www.example.com. 5 IN A 10.20.30.40
	SECTION AUTHORITY
	example.com. 10 IN NS ns.example.com.
	SECTION ADDITIONAL
	ns.example.com. 10 IN A 10.20.30.50
ENTRY_END

; Wait for the A RRSET to expire.
STEP 5 TIME_PASSES ELAPSE 6

STEP 6 QUERY
ENTRY_BEGIN
	REPLY RD
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
; expired answer will not be served due to serve-expired-client-timeout.
STEP 7 CHECK_OUT_QUERY
ENTRY_BEGIN
	MATCH qname qtype opcode
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
STEP 8 REPLY
ENTRY_BEGIN
	MATCH opcode qtype qname
	ADJUST copy_id
	; authoritative answer
	REPLY QR AA RD RA NOERROR
	SECTION QUESTION
	www.example.com. IN A
	SECTION ANSWER
	www.example.com. 5 IN A 10.20.30.40
	SECTION AUTHORITY
	example.com. 10 IN NS ns.example.com.
	SECTION ADDITIONAL
	ns.example.com. 10 IN A 10.20.30.50
ENTRY_END
; The cached NS related RRSETs will not be overwritten by the fresh answer.
; The message should have a TTL of 4 instead of 5 from above.
STEP 9 CHECK_ANSWER
ENTRY_BEGIN
	MATCH all ttl
	REPLY QR RD RA
	SECTION QUESTION
	www.example.com. IN A
	SECTION ANSWER
	www.example.com. 5 IN A 10.20.30.40
	SECTION AUTHORITY
	example.com. 4 IN NS ns.example.com.
	SECTION ADDITIONAL
	ns.example.com. 4 IN A 10.20.30.50
ENTRY_END

; Wait for the NS RRSETs to expire.
STEP 10 TIME_PASSES ELAPSE 5

STEP 11 QUERY
ENTRY_BEGIN
	REPLY RD
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
; The message should be expired, again no expired answer at this point due to
; serve-expired-client-timeout.
STEP 12 CHECK_OUT_QUERY
ENTRY_BEGIN
	MATCH qname qtype opcode
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
STEP 13 REPLY
ENTRY_BEGIN
	MATCH opcode qtype qname
	ADJUST copy_id
	REPLY QR RD RA SERVFAIL
	SECTION QUESTION
	www.example.com. IN A
ENTRY_END
; The SERVFAIL will trigger the serve-expired-client-timeout logic to try and
; replace the SERVFAIL with a possible cached (expired) answer.
; The A RRSET would be at 0TTL left (not expired) but the message should have
; been updated to use a TTL of 4 so expired by now.
; If the message TTL was not updated (bug), this message would be treated as
; non-expired and the now expired NS related RRSETs would fail sanity checks
; for non-expired messages. The result would be SERVFAIL here.
STEP 14 CHECK_ANSWER
ENTRY_BEGIN
	MATCH all ttl
	REPLY QR RD RA
	SECTION QUESTION
	www.example.com. IN A
	SECTION ANSWER
	www.example.com. 0 IN A 10.20.30.40
	SECTION AUTHORITY
	example.com. 30 IN NS ns.example.com.
	SECTION ADDITIONAL
	ns.example.com. 30 IN A 10.20.30.50
ENTRY_END

SCENARIO_END