Anyone know about DNS?

Hi All,

I'm going to ask a favor. I need some help possibly debugging my DNS
setup.

I run a web/mail server with multiple domains. The problem I have is
that sometimes people cannot contact my server. Other times it seems
to take more than 45 seconds for a page to draw. The results really
have no pattern. So, I am thinking that maybe I have something set up
wrong.

I know next to nothing about Linux configuration.

So, I was hoping that someone might help me out by suggesting which
config files need to be looked at and looking at them.

Any help is appreciated.

Thanks,

Arthur


Arthur

On 2004-10-07, Arthur <(E-Mail Removed)> wrote:
> that sometimes people cannot contact my server. Other times it seems
> to take more than 45 seconds for a page to draw.

If something happens "sometimes", by definition is not config-related.
If you have a busted configuration it _always_ work that way.

Start with trying to pinpoint when that happen and if it's a connection
related issue (no connection to the server) or is a server related
issue (connection ok but the server doesn't answer). If you can't
replicate the problem from the local network, maybe is a problem
outside your network: a busted router or routing table at your ISP
maybe.

Davide

--
If it's too good to be true, it's probably a rigged demo.
Any sufficiently advanced technology is indistinguishable from a rigged
demo.

On 8 Oct 2004 04:27:01 GMT,
Davide Bianchi <(E-Mail Removed)> wrote:


> On 2004-10-07, Arthur <(E-Mail Removed)> wrote:
>> that sometimes people cannot contact my server. Other times it seems
>> to take more than 45 seconds for a page to draw.
>
> If something happens "sometimes", by definition is not config-related.
> If you have a busted configuration it _always_ work that way.
>

Not always true. A common mistake is that the designated DNS server
for a zone isn't authoritative for that zone or doesn't exist at all.
The designated DNS server is the server referred to in the parent zone
in a NS record. These servers are commonly referred to as "lame servers".


Villy

Davide Bianchi wrote:
> On 2004-10-07, Arthur <(E-Mail Removed)> wrote:
>
>>that sometimes people cannot contact my server. Other times it seems
>>to take more than 45 seconds for a page to draw.
>
>
> If something happens "sometimes", by definition is not config-related.
> If you have a busted configuration it _always_ work that way.

Rubbish. Configuration errors are quite capable of giving intermittent
behaviour. This is especially true of DNS where a domain may have
multiple nameservers and one server doesn't get notified of zone updates
due to a configuration error.

Paul

No. ;-)

--

(This space intentionally left blank)

On 7 Oct 2004 12:26:53 -0700, Arthur wrote:
> Hi All,
>
> I'm going to ask a favor. I need some help possibly debugging my DNS
> setup.
>
> I run a web/mail server with multiple domains. The problem I have is
> that sometimes people cannot contact my server. Other times it seems
> to take more than 45 seconds for a page to draw. The results really
> have no pattern. So, I am thinking that maybe I have something set up
> wrong.

I'd need to know a lot more about your configuration. You have one
server with multiple domains. What is your connection? Does the
server resolve (correctly) when the problems occur?

The 45 seconds sound like a timeout. My guess is that somewhere up
the line there are two or three nameservers named as secondary for
your server that's never heard of it.

Does 'dig hostname' give you anything not making sense? Both from
the outside and inside of your network?

> I know next to nothing about Linux configuration.

But your DNS server runs on linux, right?

Bjørn
--
Bjørn Tore Sund "When in fear, and when in doubt;
(E-Mail Removed) Run in circles, scream and shout!"
Interaction! - Anonymous
http://www.interaction.worldcon.org.uk/