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qnd

Member

Registered: 2012-02-21

Posts: 7

[SOLVED] Router DNS change - not taking effect?

I decided to try out Google DNS (the server addresses are 8.8.4.4 and 8.8.8.8), so I set my router's (Telewell TW-EA501v3) DNS settings accordingly, and just in case did the same for the DHCP settings in the router. So both set of DNS settings in the router are the same, saved them, and restarted the router (twice by now).

Conveniently I could use thepiratebay.se to test if the change had taken effect, as TPB has been blocked in my country recently. Turns out that it just times out, which makes me think it's blocked or something is wrong with my setup or connection to Google's DNS servers.

Unfortunately, I haven't found any help on the subject, possibly because this should be a clear cut case and I just might be missing something. Results of some troubleshooting I did (per this page's instructions):

Resolv.conf (haven't touched it):

# Generated by dhcpcd from eth0
# /etc/resolv.conf.head can replace this line
domain TeleWell.gateway
nameserver 8.8.4.4
nameserver 8.8.8.8
# /etc/resolv.conf.tail can replace this line#

Commands and their results:

# traceroute -n -w 2 -q 2 -m 30 8.8.4.4:
traceroute to 8.8.4.4 (8.8.4.4), 30 hops max, 52 byte packets
 1  192.168.0.254  1.106 ms  1.083 ms
 2  139.97.9.38  12.177 ms  12.484 ms
 3  139.97.9.37  38.253 ms  11.881 ms
 4  139.97.6.250  11.863 ms  11.574 ms
 5  213.192.191.53  12.129 ms  12.160 ms
 6  213.192.184.45  18.793 ms  19.304 ms
 7  74.125.50.145  19.332 ms  18.791 ms
 8  209.85.250.192  19.104 ms  18.361 ms
 9  209.85.248.132  47.524 ms  47.942 ms
10  216.239.48.53  47.272 ms  46.593 ms
11  * *
12  8.8.4.4  47.425 ms  46.619 ms

# traceroute -n -w 2 -q 2 -m 30 thepiratebay.se
traceroute to thepiratebay.se (194.71.107.15), 30 hops max, 52 byte packets
 1  192.168.0.254  1.165 ms  1.091 ms
 2  139.97.9.38  12.286 ms  20.037 ms
 3  139.97.9.37  12.182 ms  11.541 ms
 4  139.97.6.250  11.400 ms  11.401 ms
 5  * *
 6  * *
 7  * *
 8  * *
 9  * *

$ dig @8.8.4.4 thepiratebay.se:
; <<>> DiG 9.8.1 <<>> @8.8.4.4 thepiratebay.se
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 8365
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;thepiratebay.se.               IN      A

;; ANSWER SECTION:
thepiratebay.se.        61117   IN      A       194.71.107.15

;; Query time: 49 msec
;; SERVER: 8.8.4.4#53(8.8.4.4)
;; WHEN: Tue Feb 21 09:33:37 2012
;; MSG SIZE  rcvd: 49

EDIT: Figured these might be more helpful. It seems like my requests are still going through my ISP? (I don't fully understand these things.) Elisa.net is the ISP.

# traceroute -w 2 -q 2 -m 30 8.8.4.4
traceroute to 8.8.4.4 (8.8.4.4), 30 hops max, 52 byte packets
 1  192.168.0.254 (192.168.0.254)  0.939 ms  0.949 ms
 2  1-2-1.kerker1.fi.elisa.net (139.97.9.38)  14.583 ms  11.653 ms
 3  ge1-1-0.helso-p1.fi.elisa.net (139.97.9.37)  11.535 ms  11.577 ms
 4  ae2.helpa-gw1.fi.elisa.net (139.97.6.250)  11.382 ms  50.572 ms
 5  ae1-10.bbr1.hel2.fi.eunetip.net (213.192.191.53)  12.473 ms  16.852 ms
 6  ae1-0.bbr1.sto1.se.eunetip.net (213.192.184.45)  19.089 ms  18.904 ms
 7  74.125.50.145 (74.125.50.145)  18.313 ms  18.323 ms
 8  209.85.250.192 (209.85.250.192)  18.662 ms  18.372 ms
 9  209.85.248.132 (209.85.248.132)  49.882 ms  46.973 ms
10  216.239.48.53 (216.239.48.53)  56.270 ms  47.117 ms
11  * *
12  google-public-dns-b.google.com (8.8.4.4)  46.856 ms  47.366 ms

# traceroute -w 2 -q 2 -m 30 thepiratebay.se
traceroute to thepiratebay.se (194.71.107.15), 30 hops max, 52 byte packets
 1  192.168.0.254 (192.168.0.254)  1.316 ms  1.094 ms
 2  1-2-1.kerker1.fi.elisa.net (139.97.9.38)  13.305 ms  13.144 ms
 3  ge1-1-0.helso-p1.fi.elisa.net (139.97.9.37)  11.503 ms  12.092 ms
 4  ae2.helpa-gw1.fi.elisa.net (139.97.6.250)  12.229 ms  10.802 ms
 5  * *
 6  * *
 7  * *
 8  * *

Last edited by qnd (2012-02-21 09:22:36)

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: [SOLVED] Router DNS change - not taking effect?

traceroute is for routing, not DNS. It is not surprising that the packets go through your ISP, because it is the ISP which is your link to the Internet.

I always recommend that people just run BIND. Think that Google are not evil too?

qnd

Member

Registered: 2012-02-21

Posts: 7

Re: [SOLVED] Router DNS change - not taking effect?

Just realized I didn't stop to consider or research the fact that my ISP was also ordered to block the IP addresses of TPB, rendering this as a method figure out if I'm actually using Google's DNS servers or not, useless. (I would just like to confirm if I'm actually using their servers. I'll have to find some other way.) I feel embarassed but according to forum policies this should stay here... solved.

Gcool

Member

Registered: 2011-08-16

Posts: 1,456

Re: [SOLVED] Router DNS change - not taking effect?

If you just run...

# dig www.google.com

...does the answer section also contain SERVER: 8.8.4.4#53(8.8.4.4)?

If so, your dns requests are going over the Google dns servers and everything should be fine. If you're still unable to reach a specific site (piratebay for example), then your isp is probably doing more then just a simple dns block.

---

Burninate!

qnd

Member

Registered: 2012-02-21

Posts: 7

Re: [SOLVED] Router DNS change - not taking effect?

If you just run...

# dig www.google.com

...does the answer section also contain SERVER: 8.8.4.4#53(8.8.4.4)?

If so, your dns requests are going over the Google dns servers and everything should be fine.

That it does, thanks for that! So I guess that's confirmed then. Now I also feel embarassed about marking this thread solved so quickly.

If you're still unable to reach a specific site (piratebay for example), then your isp is probably doing more then just a simple dns block.

Yup, that must be it, as far as I understand the ISP blocking the site's IPs does the job.