Skip to main content

DNS: Notes

DNS Root Servers

Domain Name System

DNS uses UDP/53 as default and TCP/53 as fallback.

nslookup

nslookup -type=txt youtube.com
nslookup -type=mx google.com

dig

dig youtube.com txt

host - DNS lookup utility

host -t txt google.com

Check PTR text record

PS C:\Users\Administrator> nslookup -type=ptr 173.82.240.78
Server:  UnKnown
Address:  2402:800:20ff:6666::1

Non-authoritative answer:
78.240.82.173.in-addr.arpa      name = mx2.practicehabits.net
PS C:\Users\Administrator>

Check DMARC text record

PS C:\Users\Administrator> nslookup -type=txt _dmarc.practicehabits.net
Server:  UnKnown
Address:  2402:800:20ff:6666::1

Non-authoritative answer:
_dmarc.practicehabits.net       text =

        "v=DMARC1; p=reject; rua=mailto:postmaster@practicehabits.net, mailto:postmaster@practicehabits.net"
PS C:\Users\Administrator> nslookup -type=txt _dmarc.2practice.xyz
Server:  UnKnown
Address:  2402:800:20ff:6666::1

*** No text (TXT) records available for _dmarc.2practice.xyz

Online tools

https://mxtoolbox.com/

https://ViewDNS.info/

DMARC Record Checker

DKIM Record Checker

DNS History Lookup

References

Practice

>>> THM | DNS Manipulation

>>> THM | DNS in Details

Popular posts from this blog

Delete files older than 365 days

I must delete IIS *.log files in  older than 365 days. D:\Logs | -W3SVC1 -W3SVC2 -... -W3SVC33 daily-delete-logfiles-older-than-365-days.cmd :: Daily delete log files older than 365 days :: Created on: 20161120 :: Created by: :: Last modified on: :: Last modified by: :: History: SET DIRLOG=E:\_scripts\Logs\ :: Echo @path to test first :: FORFILES /P D:\Logs /S /M *.log /D -365 /C "cmd /c echo @path @fdate" :: Delete files ECHO "Begin" >> %dirlog%daily-delete-logfiles.log DATE /T >> %dirlog%daily-delete-logfiles.log TIME /T >> %dirlog%daily-delete-logfiles.log FORFILES /P D:\Logs /S /M *.log /D -365 /C "cmd /c del @path" >> %dirlog%daily-delete-logfiles.log ECHO "Finished" >> %dirlog%daily-delete-logfiles.log DATE /T >> %dirlog%daily-delete-logfiles.log TIME /T >> %dirlog%daily-delete-logfiles.log :: END of script /P : Path to folder /S: recurse into subdirectories /M *.l...

SoloLearn: Learn to Code for Free!

Got a minute? You can learn to code anywhere, anytime you can with your smartphone using Sololearn.

Data Recovery Softwares

Follow 3-2-1 backup rule so you do not need these data recovery softwares.