Newbie: Router won't let me get to my server(DYNDNS)

[Kevin Darcy]

"Michael H." wrote:

> After setting up my router(DI-704) for my DSL connection, I set my
> server to a static LAN address of 192.168.0.10. I set it up as a DMZ
> in the router software.
>
> The router maintains a connection on my PPPoE account, and I have my
> DYNDNS client pointing to my server(as elba.dyndns.org among others).
> The client(DNSUpdate 2.2) reports all interfaces OK.
>
> >From my server, if I type ping elba.dyndns.org, I get DNS resolution(I
> set my router as it's DNS server, 192.168.0.1) it pings with very
> short ping times...so far so good.
>
> But when I try to access my server via a web browser from off-site,
> 139.57.XXX.XXX,(yes, I'm sure that the server is working)there's no
> response. I try
>
> ping elba.dyndns.org
>
> from a command-line(Darwin Unix) and I get:
>
> PING elba.dyndns.org (192.168.0.10): 56 data bytes
>
> then I wait a bit, and when I hit CTRL-C, I get something along the
> lines of
>
> 9 packets sent, 0 received, 100% packet loss.
>
> why can't I get any data back from the computer, even though it seems
> to be able to find the computer?
>
> It seems like the DNS is not resolving, but how did it know that
> 192.168.0.10 is my server? So if it can get there, why can't I get to
> my data? I think it's a configuration problem with my Dyndns client,
> but I'm not sure what....

elba.dyndns.org currently resolves to 64.230.98.54 on the Internet, which
is presumably your WAN address.

So, your problem may boil down to: why is your ping client resolving
elba.dyndns.org to 192.168.0.10? Do you have a "hosts" file entry for that
name? Is the resolver on your ping client pointed at some
"special" DNS server that has a different view of your domain name than
everyone else?

Hopefully you realize that 192.168.*.* addresses are non-routable, so they
should *never* work from arbitrary Internet locations. See RFC 1918 for
more details. The fact that you "wait[ed] a bit" even after seeing that
the name was resolving to a 192.168.*.* address implies that you weren't
in fact aware of this. If I misunderstood your comment, please accept my
apologies -- sometimes there's a fine line to be walked between informing
someone and condescending to them...

I suppose it's possible that this could actually be a DynDNS client issue
-- maybe the client is setting elba.dyndns.org to the WAN address
sometimes and to the LAN (192.168.0.10) address at other times. But with a
TTL (time-to-live) value of only 1 minute, it's hard for me to catch it
red-handed with the wrong address...


- Kevin