nameserver 192.168.1.100 nameserver 192.168.1.101
Table6. Resolv.conf file entries.
The domain and search criteria are optional and only useful if running authoritative DNS servers in a network. Since I am running primary and secondary, master and slave DNS servers I have both domain and search listed with dual name server addresses pointing to both of them on my local network. If in a SOHO setup, the DNS servers for the ISP maybe the preferred choice of entry here. Testing we can use nslookup or dig tools, but this is not necessary as pinging a domain should result in replies provided that the server has ICMP echo reply enabled. An example of these tools can be seen below:
root@Compaq2230s:~# ping c 5 www.google.com
PING www.l.google.com (209.85.129.147) 56(84) bytes of data.
64 bytes from fkinf147.google.com (209.85.129.147): icmp_seq=1 ttl=245 time=26.4 ms
64 bytes from fkinf147.google.com (209.85.129.147): icmp_seq=2 ttl=245 time=26.2 ms
64 bytes from fkinf147.google.com (209.85.129.147): icmp_seq=3 ttl=245 time=26.8 ms
64 bytes from fkinf147.google.com (209.85.129.147): icmp_seq=4 ttl=245 time=26.7 ms
64 bytes from fkinf147.google.com (209.85.129.147): icmp_seq=5 ttl=245 time=24.3 ms
www.l.google.com ping statistics
5 packets transmitted, 5 received, 0% packet loss, time 4004ms rtt min/avg/max/mdev = 24.331/26.115/26.820/0.916 ms
root@Compaq2230s:~# nslookup www.google.com
Server: 192.168.1.100 Address:192.168.1.100#53
Nonauthoritative answer:
www.google.comcanonical name = www.l.google.com.
Name: www.l.google.com
Address: 209.85.129.104
Name: www.l.google.com
Address: 209.85.129.147
Name: www.l.google.com
Address: 209.85.129.99
root@Compaq2230s:~# dig @192.168.1.100 www.google.com
;<<>> DiG 9.5.1P2 <<>> @192.168.1.100 www.google.com
;(1 server found)
;;global options: printcmd
;;Got answer:
;;>>HEADER<< opcode: QUERY, status: NOERROR, id: 31674
;;flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 6, ADDITIONAL: 0
;;QUESTION SECTION:
;www.google.com. |
|
| IN | A |
|
;; ANSWER SECTION: |
|
|
|
|
|
www.google.com. |
| 0 | IN | CNAME | www.l.google.com. |
www.l.google.com. | 233 | IN | A | 209.85.129.99 |
|
www.l.google.com. | 233 | IN | A | 209.85.129.104 |
|
www.l.google.com. | 233 | IN | A | 209.85.129.147 |
|
;; AUTHORITY SECTION: |
|
|
|
| |
l.google.com. | 41142 | IN | NS | b.l.google.com. |
|
l.google.com. | 41142 | IN | NS | f.l.google.com. |
|
l.google.com. | 41142 | IN | NS | d.l.google.com. |
|
l.google.com. | 41142 | IN | NS | e.l.google.com. |
|
l.google.com. | 41142 | IN | NS | g.l.google.com. |
|
l.google.com. | 41142 | IN | NS | a.l.google.com. |
|
10
