DNS take important part in internet world as resolver for domain. The problem came when we think something wrong with it. Need to examine which server is in trouble.
From this picture :
There is two dns servers :
- 202.146.178.4
- 208.67.222.222
In windows we can check which dns server that work well using nslookup.
Steps :
1. Click start -> run
type cmd dan press OK.
2. Enter DOS prompt
See this example :
C:\Documents and Settings\Administrator>nslookup
Default Server:Â dnscache1.elnus.net.id
Address:Â 202.146.178.4
> www.yahoo.com
Server:Â dnscache1.elnus.net.id
Address:Â 202.146.178.4
Non-authoritative answer:
Name:Â Â Â www.yahoo-ht3.akadns.net
Address:Â 209.131.36.158
Aliases:Â www.yahoo.com
> server 208.67.222.222
Default Server:Â resolver1.opendns.com
Address:Â 208.67.222.222
> www.detik.com
Server:Â resolver1.opendns.com
Address:Â 208.67.222.222
Non-authoritative answer:
Name:Â Â Â detik.com
Addresses:Â 202.158.66.94, 203.190.241.41, 203.190.241.43, 202.158.66.190
202.158.66.86, 203.190.241.166, 202.158.66.20
Aliases:Â www.detik.com
> help
Commands:Â Â (identifiers are shown in uppercase, [] means optional)
NAMEÂ Â Â Â Â Â Â Â Â Â Â – print info about the host/domain NAME using default server
NAME1 NAME2Â Â Â Â – as above, but use NAME2 as server
help or ?      – print info on common commands
set OPTIONÂ Â Â Â Â – set an option
all                – print options, current server and host
[no]debug          – print debugging information
[no]d2Â Â Â Â Â Â Â Â Â Â Â Â Â – print exhaustive debugging information
[no]defname        – append domain name to each query
[no]recurse        – ask for recursive answer to query
[no]search         – use domain search list
[no]vc             – always use a virtual circuit
domain=NAMEÂ Â Â Â Â Â Â Â – set default domain name to NAME
srchlist=N1[/N2/…/N6] – set domain to N1 and search list to N1,N2, etc.
root=NAMEÂ Â Â Â Â Â Â Â Â Â – set root server to NAME
retry=XÂ Â Â Â Â Â Â Â Â Â Â Â – set number of retries to X
timeout=XÂ Â Â Â Â Â Â Â Â Â – set initial time-out interval to X seconds
type=XÂ Â Â Â Â Â Â Â Â Â Â Â Â – set query type (ex. A,ANY,CNAME,MX,NS,PTR,SOA,SRV)
querytype=XÂ Â Â Â Â Â Â Â – same as type
class=XÂ Â Â Â Â Â Â Â Â Â Â Â – set query class (ex. IN (Internet), ANY)
[no]msxfr          – use MS fast zone transfer
ixfrver=XÂ Â Â Â Â Â Â Â Â Â – current version to use in IXFR transfer request
server NAMEÂ Â Â Â – set default server to NAME, using current default server
lserver NAMEÂ Â Â – set default server to NAME, using initial server
finger [USER]Â Â – finger the optional NAME at the current default host
root           – set current default server to the root
ls [opt] DOMAIN [> FILE] – list addresses in DOMAIN (optional: output to FILE)
-a         - list canonical names and aliases
-d         - list all records
-t TYPEÂ Â Â Â -Â list records of the given type (e.g. A,CNAME,MX,NS,PTR etc.)
view FILE          – sort an ‘ls’ output file and view it with pg
exit           – exit the program
> server 208.67.222.222
Default Server:Â resolver1.opendns.com
Address:Â 208.67.222.222
> lserver 202.146.178.4
Default Server:Â dnscache1.elnus.net.id
Address:Â 202.146.178.4
>
To switch dns server just type command :
server ip dns server
To switch back previous dns server type :
lserver ip dns server