[CentOS] Re: OT: anything in CentOS 5.2 that uses opendns.com
when browsing web?
lmmailinglists at gmail.com
Sat Jul 12 22:57:00 UTC 2008
On 7/11/08, Scott Silva <ssilva at sgvwater.com> wrote:
>> Question: Awhile ago, I got into the configuration settings for our
>> ZTE ADSL Modem.
>> For the change to me having my own Caching DNS Server, in the settings
>> for the ADSL modem at this time, using the DNS servers at our ISP:
>> Primary DNS Server 188.8.131.52
>> Secondary DNS Server 184.108.40.206
>> When I think I am ready to test the change I make to IPCop setting(s),
>> should I set those to 0.0.0.0. so I can use my own DNS Server ? Or.
>> leave those spaces blank? Or, leave them as they are now? Thank you,
>> very much, for your time and help, which are greatly appreciated!
> It looks as if your ADSL modem is in NAT mode, so it is acting like a very
> simple router already. What settings does it actually have?
Scott: Which settings in the ADSL Modem are you interested in? There
are quite a few settings available in the web interface. If you tell
me which settings are of interest, I'll get them for you.
ADSL Port Enable
Downstream Line Rate 2047
Upstream Line Rate 507
LAN IP Address 192.168.1.1
Default Gateway 220.127.116.11
Primary DNS Server 18.104.22.168
Secondary DNS Server 22.214.171.124
ADSL line status
Current adsl line status is as the below.
Line Mode ADSL2+ Line State Show Time
Line Up Time Duration 00:05:28:31 System Up Time 00:05:28:39
Line Downstream Rate 2047 Line Upstream Rate 507
Latency Type Fast Line Coding Trellis On
Noise Margin 31.6 Line Attenuation 19.5
Output power 22.0 Attainable Line Rate 17628
Line Up Count 1 Status No Defect
If you note any problems in the quality of the line, the phone company
people were working in our subdivision a few weeks ago and they
detected a problem, with a long cable we have, underground, about 100
(?) meters in the street to their box. Apparently, 2 cables are
touching. They mentioned running a new cable in the air, instead of
underground. I was surprised that they found this problem, because at
the same time, on speedtest.net I got a Download speed of 1780 from a
server in Orlando and our contract with our ISP is for 550, so I was
happy with the speed they were providing to us.
> I think you can leave those settings alone, as they only will be used if you
> point DNS settings at the modems ip address. If you set your IPcop box at
> 127.0.0.1 it should seek out to the root servers by itself.
Cool. It sounds like all I need to do is change the one setting in the
IPCop box and if all goes well, my Caching DNS Server is up and
running. I will try it, ASAP, on our backup IPCop box. If I get up
*early* Sunday morning, I will try it then.
> As I posted earlier, you will have to poke around in the ipcop setup menu to
> get dhcp and custom DNS settings both working.
That's why I want to do it on the backup IPCop box. If it stops
working, my VIP users can continue using the IPCop box that works and
I don't have irate users. :-) The IPCop box is our "Production"
> I just played with one of my test vmware ipcop images and set it to dhcp on
> our internal network (which should simulate your natted connection through
> your adsl modem) for the red interface and I was able to dig +trace
> with proper answers. So it is possible to get it working unless your ISP
> blocks DNS queries to anywhere else but their own servers.
Hoping they are not blocking those DNS queries or any other traffic.
I just SSH'd into the IPCop box:
root at ipcop:~ # dig gmail.com
; <<>> DiG 9.4.0 <<>> gmail.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29247
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 13, ADDITIONAL: 11
;; QUESTION SECTION:
;gmail.com. IN A
;; ANSWER SECTION:
gmail.com. 27 IN A 126.96.36.199
gmail.com. 27 IN A 188.8.131.52
gmail.com. 27 IN A 184.108.40.206
;; AUTHORITY SECTION:
com. 152960 IN NS a.gtld-servers.net.
com. 152960 IN NS f.gtld-servers.net.
com. 152960 IN NS m.gtld-servers.net.
com. 152960 IN NS b.gtld-servers.net.
com. 152960 IN NS j.gtld-servers.net.
com. 152960 IN NS g.gtld-servers.net.
com. 152960 IN NS l.gtld-servers.net.
com. 152960 IN NS i.gtld-servers.net.
com. 152960 IN NS c.gtld-servers.net.
com. 152960 IN NS e.gtld-servers.net.
com. 152960 IN NS k.gtld-servers.net.
com. 152960 IN NS h.gtld-servers.net.
com. 152960 IN NS d.gtld-servers.net.
;; ADDITIONAL SECTION:
j.gtld-servers.net. 172736 IN A 220.127.116.11
b.gtld-servers.net. 172737 IN A 18.104.22.168
b.gtld-servers.net. 172737 IN AAAA 2001:503:231d::2:30
i.gtld-servers.net. 172737 IN A 22.214.171.124
l.gtld-servers.net. 172736 IN A 126.96.36.199
d.gtld-servers.net. 172736 IN A 188.8.131.52
c.gtld-servers.net. 172791 IN A 184.108.40.206
g.gtld-servers.net. 172736 IN A 220.127.116.11
h.gtld-servers.net. 172737 IN A 18.104.22.168
k.gtld-servers.net. 172736 IN A 22.214.171.124
a.gtld-servers.net. 172736 IN A 126.96.36.199
;; Query time: 35 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Sat Jul 12 17:52:10 2008
;; MSG SIZE rcvd: 487
root at ipcop:~ #
root at ipcop:~ # dig +trace gmail.com
; <<>> DiG 9.4.0 <<>> +trace gmail.com
;; global options: printcmd
;; connection timed out; no servers could be reached
root at ipcop:~ #
Possibly after I have the DNS Caching working, dig +trace will work.
Thanks much! Lanny
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