• DNS
    • ➟ Preliminaries 
> dig learn.mi.hdm-stuttgart.de

; <<>> DiG 9.16.1-Ubuntu <<>> learn.mi.hdm-stuttgart.de
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63891
...
;; ANSWER SECTION:
learn.mi.hdm-stuttgart.de. 6593	IN	A	141.62.64.28

;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) ...
> dig +noall +answer www.hdm-stuttgart.de
www.hdm-stuttgart.de.	3600	IN	A	141.62.1.53
www.hdm-stuttgart.de.	3600	IN	A	141.62.1.59
Record Explanation
A IPV4 Host address
AAAA IPv6 host address
ALIAS Auto resolved alias
CNAME Canonical name for an alias
MX Mail eXchange
NS Name Server
PTR Pointer
SOA Start Of Authority
SRV location of service
TXT Descriptive text 
dig +noall +answer -t NS hdm-stuttgart.de
hdm-stuttgart.de.	3600	IN	NS	iz-net-4.hdm-stuttgart.de.
hdm-stuttgart.de.	3600	IN	NS	dns3.belwue.de.
hdm-stuttgart.de.	3600	IN	NS	iz-net-3.hdm-stuttgart.de.
hdm-stuttgart.de.	3600	IN	NS	dns1.belwue.de.
hdm-stuttgart.de.	3600	IN	NS	iz-net-2.hdm-stuttgart.de.
  • DNS
    • ➟ Exercises
      • ➟ SDI exercises related DNS server

  • Dedicated lecture related DNS server nssdi.mi.hdm-stuttgart.de.

  • One subdomain per group e.g. g7.sdi.mi.hdm-stuttgart.de corresponding to group 7.

  • Zone edits require a subdomain specific hmac secret key being provided as dnsupdate.sec file in your personal group entry below the SDI course: 

    hmac-sha256:mykey.g7:I5sDDS3L1BU...

    Note

    The per zone secrets are being created using tsig-keygen. The value appearing here does not reflect a production setting.

  • Edits become globally visible. Mind the TTL setting: A higher value means you'll have to wait longer until error corrections become visible. 

$ export HMAC=hmac-sha256:mykey.g7:YXWSeh3l... 
$ dig @nssdi.mi.hdm-stuttgart.de -y $HMAC -t AXFR g7.sdi.mi.hdm-stuttgart.de 
...
g7.sdi.mi.hdm-stuttgart.de. 86400 IN	SOA	nssdi.mi.hdm-stuttgart.de. goik.hdm-stuttgart.de. ...
docu.g7.sdi.mi.hdm-stuttgart.de. 5000 IN CNAME	www.g7.sdi.mi.hdm-stuttgart.de.
manual.g7.sdi.mi.hdm-stuttgart.de. 5000 IN CNAME www.g7.sdi.mi.hdm-stuttgart.de.
nextcloud.g7.sdi.mi.hdm-stuttgart.de. 5000 IN CNAME www.g7.sdi.mi.hdm-stuttgart.de.
...
export HMAC=hmac-sha256:mykey.g7:YXWSeh3l... 

goik>nsupdate -y $HMAC
> server nssdi.mi.hdm-stuttgart.de
> update add vm2.g7.sdi.mi.hdm-stuttgart.de 86400 A 141.62.75.114
> send
> quit
goik>dig +noall +answer @nssdi.mi.hdm-stuttgart.de vm2.g7.sdi.mi.hdm-stuttgart.de
vm2.g7.sdi.mi.hdm-stuttgart.de. 86400	IN A	141.62.75.114
$ nsupdate -y $HMAC
> server nssdi.mi.hdm-stuttgart.de
> update delete admin.g3.sdi.mi.hdm-stuttgart.de. 3600 IN	CNAME	www.g3.sdi.mi.hdm-stuttgart.de.
> update add admin.g3.sdi.mi.hdm-stuttgart.de. 7200 IN	CNAME	www.g3.sdi.mi.hdm-stuttgart.de.
> send
> quit

Note

Examples at DNS Updates with nsupdate