DNS troubleshooting tools and tips - nslookp

if you are on Windows, dig is not there, you can do most DNS query through nslookup.

to see the DNS cache on your local server,  run “ipconfig /displayDNS”

same thing, ipconfig /flushDNS to purge the cache.

to see name server of a giving domain

to see all infomration like root server, try nslookup , set all

to see mx record of amazon.

to see the spf record?

what about debug information

to see all information

to see all the ips of a domain or even this history.

https://www.virustotal.com/en/domain/dl.dropbox.com/information/

DNS troubleshooting tools and tips - dig

To see top level Name Servers,  dig –t ns com

If we want to see what’s are the name server of Google by asking any top level com servers.

now we can ask any nameserver of google, what’s are the ip of www.google.com

we can also using host command to get the ip or alias information

we can see the alias gmail.google.com

if we want to see some debug information. we can put debug there

[~]dig +trace  -t mx  dropbox.com ; <<>> DiG 9.8.3-P1 <<>> +trace -t mx dropbox.com ;; global options: +cmd .            15634    IN    NS    a.root-servers.net. .            15634    IN    NS    b.root-servers.net. .            15634    IN    NS    c.root-servers.net. .            15634    IN    NS    d.root-servers.net. .            15634    IN    NS    e.root-servers.net. .            15634    IN    NS    f.root-servers.net. .            15634    IN    NS    g.root-servers.net. .            15634    IN    NS    h.root-servers.net. .            15634    IN    NS    i.root-servers.net. .            15634    IN    NS    j.root-servers.net. .            15634    IN    NS    k.root-servers.net. .            15634    IN    NS    l.root-servers.net. .            15634    IN    NS    m.root-servers.net. ;; Received 228 bytes from 8.8.8.8#53(8.8.8.8) in 29 ms com.            172800    IN    NS    a.gtld-servers.net. com.            172800    IN    NS    b.gtld-servers.net. com.            172800    IN    NS    c.gtld-servers.net. com.            172800    IN    NS    d.gtld-servers.net. com.            172800    IN    NS    e.gtld-servers.net. com.            172800    IN    NS    f.gtld-servers.net. com.            172800    IN    NS    g.gtld-servers.net. com.            172800    IN    NS    h.gtld-servers.net. com.            172800    IN    NS    i.gtld-servers.net. com.            172800    IN    NS    j.gtld-servers.net. com.            172800    IN    NS    k.gtld-servers.net. com.            172800    IN    NS    l.gtld-servers.net. com.            172800    IN    NS    m.gtld-servers.net. ;; Received 489 bytes from 128.63.2.53#53(128.63.2.53) in 144 ms dropbox.com.        172800    IN    NS    ns-564.awsdns-06.net. dropbox.com.        172800    IN    NS    ns-315.awsdns-39.com. dropbox.com.        172800    IN    NS    ns-1162.awsdns-17.org. dropbox.com.        172800    IN    NS    ns-1949.awsdns-51.co.uk. ;; Received 198 bytes from 192.52.178.30#53(192.52.178.30) in 167 ms dropbox.com.        3600    IN    MX    1 aspmx.l.google.com. dropbox.com.        3600    IN    MX    10 aspmx2.googlemail.com. dropbox.com.        3600    IN    MX    10 aspmx3.googlemail.com. dropbox.com.        3600    IN    MX    5 alt1.aspmx.l.google.com. dropbox.com.        3600    IN    MX    5 alt2.aspmx.l.google.com. dropbox.com.        172800    IN    NS    ns-1162.awsdns-17.org. dropbox.com.        172800    IN    NS    ns-1949.awsdns-51.co.uk. dropbox.com.        172800    IN    NS    ns-315.awsdns-39.com. dropbox.com.        172800    IN    NS    ns-564.awsdns-06.net. ;; Received 296 bytes from 205.251.194.52#53(205.251.194.52) in 21 ms