[Opera-Linux] Flushing the DNS cache?

[Eirik Byrkjeflot Anonsen]

Kenneth Crudup <kenny at panix.com> writes:

>> On Tue, 16 Dec 2008 17:39:56 +0100, Kenneth Crudup <kenny at panix.com> wrote:
>>
>> >
>> > On Tue, 16 Dec 2008, Herman Robak wrote:
>
>> > I'm on a laptop, and can be on 3 or 4 disparate networks in one day and
>> > have been bitten by this issue. What's this explicit workaround?
>
> On Tue, 16 Dec 2008, Herman Robak wrote:
>
>>   If it keeps happening to the same server, put it in /etc/hosts.txt
>
> It ain't that simple, though. And that won't solve a problem like this:
>
> operapluginwrapper is now taking up 75% of my CPU time, spinning somewhere.
> Doing a "lsof -p" on it shows this excerpt:
>
> ----
> operaplug 15946 kenny   44u  IPv4             310496                UDP 192.168.126.122:46378->LOCALNET-GATEWAY:domain
> operaplug 15946 kenny   45u  IPv4             310495                UDP 192.168.126.122:50187->LOCALNET-GATEWAY:domain
> operaplug 15946 kenny   46u  IPv4             310499                UDP 192.168.126.122:60787->LOCALNET-GATEWAY:domain
> <snip about 20 more of these>
> operaplug 15946 kenny  171u  IPv4             310489                UDP 192.168.126.122:40290->LOCALNET-GATEWAY:domain
> operaplug 15946 kenny  174u  IPv4             310492                UDP 192.168.126.122:37282->LOCALNET-GATEWAY:domain
> operaplug 15946 kenny  176u  IPv4             310506                UDP 192.168.126.122:50020->LOCALNET-GATEWAY:domain
> ----
>
> Now, "LOCALNET-GATEWAY" is the DNS server of the place I was connected to
> *at the previous network* ; you can't get there from where I'm plugged
> into now, and another server is serving DNS entries where I am currently.
>
> So, what do I do here?

Complain to adobe?  (Assuming this is flash or acrobat, of course).

Or just turn off plug-in support.  You may find that an improvement to
the web in general :)  (Unless you're addicted to youtube...)

I'm pretty sure operapluginwrapper doesn't do anything network-related
itself.  It shouldn't have any reason to.  So I assume it is the
plug-in itself that does it.  And I don't think we can do anything
about that.  Unless the plug-in obtains the address of the dns server
from opera.  But I don't think opera knows what the address of the dns
server is on any reasonably sane system (i.e. one that we believe has
a working host resolver.)

We don't use dns for anything but simple host resolution (as far as I
know), and for that purpose doing anything else than using the system
host resolver is utterly broken.

eirik