Browser issue accesing server with dynamic IP

[K4CalDisplay]

I've a little web server running on a NAS at home that I want to access with the Kindle 4 NT webbrowser (to display a calender). My router uses DynDNS so that I can access it via a URL like example.homeftp.net. The connection to the ISP is shortly interrupted every 24 hours so that the server gets a new IP every day.
When loading the site with the Kindle browser it works only as long as the Server IP doesn't change. After the IP changes the Kindle browser cannot access the server. Rebooting the Kindle does solve this problem for the next day. So my preliminary conclusion is that the browser doesn't respect the TTL information from the DNS server and caches the IP for a URL "forever".

Has anyone else observed this behavior and solved it?
Is there a configuration file entry that disables DNS caching?

I am using firmware 4.1.1 (jailbreaked with usbNetwork access).

[knc1]

Have you examined the "lifetime" field of that DNS return?
It might just be set for longer than you ISP keeps it up.

[K4CalDisplay]

Originally Posted by knc1

Have you examined the "lifetime" field of that DNS return?
It might just be set for longer than you ISP keeps it up.

According to DynDNS the lifetime is set to 60 sec.
Other browsers do not show this behavior (I've tried Safari on iOS and Mac as well as Firefox and IE on W7). Is there a simple way to display the DNS return?

[twobob]

[root@kindle root]# ping -4 google.com

PING google.com (173.194.34.103): 56 data bytes
64 bytes from 173.194.34.103: seq=0 ttl=52 time=13.798 ms

??

so ping K4CalDisplay.dyndns.org (or whatever)

as shown here

[root@kindle root]# ping xxx.dyndns.org

PING xxx.dyndns.org (92.242.132.15): 56 data bytes

for example

[knc1]

Originally Posted by K4CalDisplay

According to DynDNS the lifetime is set to 60 sec.
Other browsers do not show this behavior (I've tried Safari on iOS and Mac as well as Firefox and IE on W7). Is there a simple way to display the DNS return?

But what is it actually set to?

I.E:

core2quad tmp # dig google.com

; <<>> DiG 9.7.3 <<>> google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3927
;; flags: qr rd ra; QUERY: 1, ANSWER: 11, AUTHORITY: 4, ADDITIONAL: 4

;; QUESTION SECTION:
;google.com.            IN    A

;; ANSWER SECTION:
google.com.        300    IN    A    74.125.228.5
- - - - -

300 seconds

Now try that with **your** dyna-dns name using the DNS server that your ISP provides you.

The lifetime field may not be what dyna-dns claims it is, or it may be getting re-written somewhere.

[twobob]

Like so...

; <<>> DiG 9.8.1-P1 <<>> xxx.dyndns.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58145
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;xxx.dyndns.org. IN A

;; ANSWER SECTION:
xxx.dyndns.org. 20 IN A 92.242.132.15

;; Query time: 32 msec
;; SERVER: 192.168.1.254#53(192.168.1.254)
;; WHEN: Sat Feb 16 23:34:32 2013
;; MSG SIZE rcvd: 52

20 it reckons

[twobob]

You know....

I kind of recall this being a problem...

but IIRC the kindle does actually return the right IP if you ping from the command.

It's the browser that caches the IP I think.

hmm. I might be remembering that wrong. but I think I am right.

perhaps a lateral solution is required.

simply inject the CORRECT IP for the URLs:80 into the browser? somehow? every 5 mins?



something like that.

[K4CalDisplay]

Ping works well, but the browser is not able to connect to the server:

[root@kindle /]# ping example.homeftp.net
PING example.homeftp.net (79.217.45.123): 56 data bytes
64 bytes from 79.217.45.123: seq=0 ttl=63 time=2.111 ms
64 bytes from 79.217.45.123: seq=1 ttl=63 time=5.714 ms
64 bytes from 79.217.45.123: seq=2 ttl=63 time=5.166 ms
64 bytes from 79.217.45.123: seq=3 ttl=63 time=5.034 ms

(URL and IP changed for privacy reasons)

[knc1]

Originally Posted by K4CalDisplay

Ping works well, but the browser is not able to connect to the server:

[root@kindle /]# ping example.homeftp.net
PING example.homeftp.net (79.217.45.123): 56 data bytes
64 bytes from 79.217.45.123: seq=0 ttl=63 time=2.111 ms
64 bytes from 79.217.45.123: seq=1 ttl=63 time=5.714 ms
64 bytes from 79.217.45.123: seq=2 ttl=63 time=5.166 ms
64 bytes from 79.217.45.123: seq=3 ttl=63 time=5.034 ms

(URL and IP changed for privacy reasons)

Great news -
Now please answer my question about what dig returns.

This problem would get solved faster if you would share what you already know about the problem, without us having to pull each fact out of you, one post at a time.

[K4CalDisplay]

Thanks for your quick help.
dig returns a lifetime of "60" in the ANSWER SECTION

[twobob]

Originally Posted by K4CalDisplay

Ping works well, but the browser is not able to connect to the server:

[root@kindle /]# ping example.homeftp.net
PING example.homeftp.net (79.217.45.123): 56 data bytes
64 bytes from 79.217.45.123: seq=0 ttl=63 time=2.111 ms
64 bytes from 79.217.45.123: seq=1 ttl=63 time=5.714 ms
64 bytes from 79.217.45.123: seq=2 ttl=63 time=5.166 ms
64 bytes from 79.217.45.123: seq=3 ttl=63 time=5.034 ms

(URL and IP changed for privacy reasons)

Yeah that's how I remember it going down. annoyance