[BlueOnyx:18772] Re: Gneric question on 5208R DNS

[Larry Smith]

On Fri December 11 2015 00:53, Michael Stauber wrote:
> Hi Larry,
>
> > At the same time (currently) the GUI page still shows "This screen would
> > normally display"...
>
> Ok. So the server can resolve DNS. Outgoing connections (to port 80)
> also seem to work in general. Just not through the GUI.
>
> Whenever the GUI needs to make an HTTP(S) connection to the outside such
> as when polling the RSS feed or when "talking" with NewLinQ it uses the
> PHP "curl" extension.
>
> Usually Curl is then used in two stages:
>
> 1.) The function areWeOnline() checks if an outgoing connection can be
> made. This covers the check if DNS works, too.
>
> 2.) The function get_data() is used to make an HTTP or HTTPS GET
> connection to the specified URL.
>
> You find that code here in SVN:
>
> http://devel.blueonyx.it/trac/browser/BlueOnyx/5209R/platform/alpine.mod/ci
>/application/helpers/blueonyx_helper.php
>
> Line 543 to 585.
>
> I think I know what the problem *might* be:
>
> The function areWeOnline() uses a 10 second timeout. The function
> get_data() uses a 5 second timeout. If no valid response happens within
> that timeframe, then the connection attempt is aborted and the
> connection failure message is shown. We use short timeouts to prevent
> that connection problems (like to the RSS feed) slow the loading of the
> GUI down.
>
> I suspect that the 5 second timeout is too short for you and your server
> needs longer to make the request. Hence the polling of the news (or
> connections to NewLinQ) fail. If you use your own DNS server, then this
> works, because the response succeeds before the timeout happens.
>
> To test this please do this:
>
> Edit the file
> /usr/sausalito/ui/chorizo/ci/application/helpers/blueonyx_helper.php and
> find the line 548. It should read like this:
>
>         $awo_timeout = "10";
>
> Change the 10 to 30.
>
> A bit below in line 572 you find this:
>
> 	    $timeout = 5;
>
> Change the 5 to a 30. Then save the changes and try to access the GUI
> and see if the "BlueOnyx News" shows the news from the RSS feed.
>
> I suspect that this will then work. In that case it's indeed an issue
> with the short timeout. Which seems to indicate that the DNS servers
> you're using might be responding pretty slow.
>
> While you're on the console, please report back what this command shows:
>
> time nslookup www.blueonyx.it
>
> It should show something like this:
>
> [root at 5209r ]# time nslookup www.blueonyx.it
> Server:         208.67.251.180
> Address:        208.67.251.180#53
>
> Non-authoritative answer:
> Name:   www.blueonyx.it
> Address: 38.114.102.4
>
>
> real    0m0.139s
> user    0m0.006s
> sys     0m0.006s
>
> The interesting part is at the end. In the line "real" it shows how long
> it took to execute the command and get a result. In your case it might
> need 3-4 seconds, which (combined with the actual GET request) then
> causes the timeout.

Michael,

  Sincerely appreciate all the research.

1.  Made the changes you mentioned above (line 548, 572), changed both to 30.

2.  Changed from the intro page to software updates, still get the "this page 
would"; changed back to the intro (Server Management) page and get the
"this page would".

3.  Ran the time nslookup using three different servers (times are virtually 
identical)

time nslookup www.blueonyx.it
Server:         65.255.100.6
Address:        65.255.100.6#53

Non-authoritative answer:
Name:   www.blueonyx.it
Address: 38.114.102.4


real    0m0.251s
user    0m0.000s
sys     0m0.002s

4.  Went to Network services, DNS, clicked enable.  Went back to the BlueOnyx
News tab and it displays the news feed.

5.  Re-ran the nslookup:

time nslookup www.blueonyx.it
Server:         65.255.100.6
Address:        65.255.100.6#53

Non-authoritative answer:
Name:   www.blueonyx.it
Address: 38.114.102.4


real    0m0.003s
user    0m0.000s
sys     0m0.002s

-- 
Larry Smith
lesmith at ecsis.net