Preliminaries


Figure 951. DNS query commands Slide presentation

Figure 952. DNS forward lookup Slide presentation
> 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) ...

Figure 953. Display A-record result only Slide presentation
> 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

Figure 954. Important record types Slide presentation
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

Figure 955. Name Servers: Query type NS Slide presentation
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.