Alternative to SOA?

Question

So I've been looking at No SOA record -- what are the implications? which shows that SOA records aren't obligatory but a good idea.

As of today - 0-21.ru doesn't have an SOA record. It has a Whois record so is there an alternative way to tracking down through dig that this domain is in fact alive (even though I guess technically its not) when it doesn't have an SOA record?

The examples in the question I reference would still require knowing what the nameserver is for the domain.

1) A domain can be registered but not published because it doesn't have nameservers or is on hold; this is nothing extraordinary and 2) "so is there an alternative way to tracking down through dig that this domain is in fact alive" query the parent nameservers to see if there is a delegation or not, as Håkan Lindqvist did in its reply; that way you know if the registry delegates the name to some nameserver or not (irrespective to the correct working of those nameservers) — Patrick Mevzek, Jul 04 '20 at 19:06

score 2 · Accepted Answer · answered Jul 03 '20 at 10:55

As per the spec each zone must have a SOA record, even though the usage is somewhat situational.
I suppose what you read a bit too much into in the answers to the other question is that, while it's not optional, if you were to violate the spec in this regard (I see no reason why you would want to) it will only break some things, not everything.

From what I can see at this time, the statement 0-21.ru doesn't have an SOA record is not obviously true.

The actual situation at this time seems to be that all the nameservers for 0-21.ru are unresponsive, making it impossible to look up any records at all. Ie, it's not possible to tell if there is a SOA record or not.

As for the other aspect of your question, you could check for the existence of a delegation in the parent zone.

Eg dig +trace +all 0-21.ru NS would show the chain of delegations. Normally you would see the responses all the way to the authoritative nameservers, but in this case it currently ends at delegation from the ru nameservers as the authoritative servers for 0-21.ru are MIA.

Or, for that matter, if you know the nameservers of the parent zone (in this case ru) you could do eg:

$ dig @d.dns.ripn.net 0-21.ru +norec

; <<>> DiG 9.11.20-RedHat-9.11.20-1.fc32 <<>> @d.dns.ripn.net 0-21.ru +norec
; (2 servers found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 52492
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 3

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;0-21.ru.                       IN      A

;; AUTHORITY SECTION:
0-21.ru.                345600  IN      NS      ns1.0-21.ru.
0-21.ru.                345600  IN      NS      ns2.0-21.ru.

;; ADDITIONAL SECTION:
ns1.0-21.ru.            345600  IN      A       185.242.84.104
ns2.0-21.ru.            345600  IN      A       185.242.84.105

;; Query time: 80 msec
;; SERVER: 2001:678:18:0:194:190:124:17#53(2001:678:18:0:194:190:124:17)
;; WHEN: Fri Jul 03 10:54:24 UTC 2020
;; MSG SIZE  rcvd: 104

$

To see that there does indeed exist a delegation.

Alternative to SOA?

1 Answers1