There are several tools for DNS debugging which offer you more or less information. Most of the time the more simple ones, like host oder nslookup will be sufficient.
host
simple DNS lookup utility.
>host heise.de
heise.de has address 193.99.144.80
heise.de has IPv6 address 2a02:2e0:3fe:1001:302::
heise.de mail is handled by 10 relay.heise.de.
nslookup
query Internet domain name servers. Nslookup has two modes: interactive and non-interactive.
>nslookup heise.de
Server: 146.254.160.30
Address: 146.254.160.30#53
Non-authoritative answer:
Name: heise.de
Address: 193.99.144.80
Name: heise.de
Address: 2a02:2e0:3fe:1001:302::
When a domain name is given, the non-interactive mode is used. Call nslookup without a url to start interactive mode. With interactive mode you just have to type in domain names and press enter to get the infos.
The Server in the first line is your DNS resolver. To use a specific one, you can call nslookup like this:
>nslookup heise.de 8.8.8.8
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
Name: heise.de
Address: 193.99.144.80
Name: heise.de
Address: 2a02:2e0:3fe:1001:302::
dig
- flexible tool for interrogating DNS name servers ( How to use dig Show archive.org snapshot )
- way more verbose than
hostandnslookup - without further parameters:
- the "QUESTION SECTION" repeats what you asked for
- the "ANSWER SECTION" shows the IP
- the "AUTHORITY SECTION" lists the authoritative names servers, therefore tells you which servers resolve the domain to a IP. It also lists the time to live (TTL), therefore how long that entry will be valid.
- the "ADDITIONAL SECTION" shows information about the authoritative name servers.
>dig heise.de
; <<>> DiG 9.11.3-1ubuntu1.11-Ubuntu <<>> heise.de
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 38907
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 13, ADDITIONAL: 24
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;heise.de. IN A
;; ANSWER SECTION:
heise.de. 2958 IN A 193.99.144.80
;; AUTHORITY SECTION:
. 34424 IN NS k.root-servers.net.
. 34424 IN NS e.root-servers.net.
. 34424 IN NS a.root-servers.net.
. 34424 IN NS m.root-servers.net.
. 34424 IN NS i.root-servers.net.
. 34424 IN NS j.root-servers.net.
. 34424 IN NS b.root-servers.net.
. 34424 IN NS d.root-servers.net.
. 34424 IN NS l.root-servers.net.
. 34424 IN NS c.root-servers.net.
. 34424 IN NS f.root-servers.net.
. 34424 IN NS h.root-servers.net.
. 34424 IN NS g.root-servers.net.
;; ADDITIONAL SECTION:
a.root-servers.net. 125551 IN A 198.41.0.4
b.root-servers.net. 344076 IN A 199.9.14.201
b.root-servers.net. 150095 IN AAAA 2001:500:200::b
c.root-servers.net. 344082 IN A 192.33.4.12
c.root-servers.net. 344082 IN AAAA 2001:500:2::c
d.root-servers.net. 344108 IN A 199.7.91.13
d.root-servers.net. 344108 IN AAAA 2001:500:2d::d
e.root-servers.net. 433387 IN A 192.203.230.10
e.root-servers.net. 460740 IN AAAA 2001:500:a8::e
F.root-servers.net. 344079 IN A 192.5.5.241
g.root-servers.net. 344065 IN A 192.112.36.4
g.root-servers.net. 133895 IN AAAA 2001:500:12::d0d
h.root-servers.net. 344063 IN A 198.97.190.53
i.root-servers.net. 344189 IN A 192.36.148.17
i.root-servers.net. 344189 IN AAAA 2001:7fe::53
J.root-servers.net. 344171 IN A 192.58.128.30
J.root-servers.net. 134495 IN AAAA 2001:503:c27::2:30
K.root-servers.net. 344126 IN A 193.0.14.129
K.root-servers.net. 169296 IN AAAA 2001:7fd::1
L.root-servers.net. 344217 IN A 199.7.83.42
L.root-servers.net. 344217 IN AAAA 2001:500:9f::42
M.root-servers.net. 344098 IN A 202.12.27.33
M.root-servers.net. 344098 IN AAAA 2001:dc3::35
;; Query time: 23 msec
;; SERVER: 146.254.160.30#53(146.254.160.30)
;; WHEN: Thu Apr 09 11:37:21 CEST 2020
;; MSG SIZE rcvd: 762
Posted by Judith Roth to makandra dev (2021-01-25 09:05)