Re: network issue
On Saturday 18 October 2025 04:24:55 am Joe wrote:
> On Fri, 17 Oct 2025 21:06:37 -0400
> "Roy J. Tellason, Sr." <roy@rtellason.com> wrote:
>
> > On Thursday 16 October 2025 04:26:37 pm Joe wrote:
> > > On Thu, 16 Oct 2025 15:28:53 -0400
> > > "Roy J. Tellason, Sr." <roy@rtellason.com> wrote:
> > >
> > > > This isn't strictly debian-related, so if there's a better place
> > > > for this feel free to point me at it and I'll try there...
> > > >
> > > > Back when my LAN was a workstation and a DSL modem, and a bit
> > > > later on a routher/firewall was added, and a server, then
> > > > later on a second workstation. Wifi was an old (now older and
> > > > very flaky) AP. These days wifi is also provided by the "modem"
> > > > (Hugesnet, who is completely useless for help on this) and it's
> > > > dual band and seems overall faster.
> > > >
> > > > The problem is when I'm using that wifi I have no access to my
> > > > local server, I can only get to it by way of the old flaky AP
> > > > that's internal to the LAN.
> > > >
> > > > Particulars: The "modem" is 192.168.1.1, the WAN side of the
> > > > router is 192.168.1.2, the server on the other side of the
> > > > router is 192.168.0.1, and the workstations get DHCP addresses
> > > > assigned when they connect, as do any devices (a couple of
> > > > phones and a tablet) that connect to the wifi. Is there any
> > > > simple way to get that external wifi to point to my internal
> > > > server when a 192.168.x.x address is used?
> > > >
> > > >
> > >
> > > Yes, but it may be a bit involved. Firstly the firewall must be
> > > opened to allow the ports you want to use on the server to pass
> > > inward through the router if it isn't using NAT.
> > >
> > > If the router is doing NAT it will be necessary to create port
> > > forwarding rules in the router to direct those ports to the
> > > server's IP address. This should automatically create the right
> > > firewall rules.
> > >
> > > If the router does not do NAT, the modem will need to be given an
> > > additional route, telling it that the route to network 192.168.0.0
> > > is via the gateway 192.168.1.2.
> >
> > That looks like what I'll need to do. Going into the admin login on
> > that device, I do Advanced Setup -> Routing -> Static Route, had to
> > enable that, added one for 192.168.0.1 (server), gateway of
> > 192.168.1.2 (router's "Internet port"), and LAN rather than WAN.
> > Saved the changes, and it doesn't work. The connection just times
> > out.
> > > Finally, if NAT is used on the router, you will need to address the
> > > server as if it was the router i.e. 192.168.1.2 and if not, then use
> > > the server's own IP address.
> > >
> > > It all depends on whether the router is just a plain router, or
> > > whether it is using NAT. Your use of the term 'WAN' suggests it is
> > > a cable router, using NAT by default.
> >
> > Actually that port is labeled "Internet", it's what used to connect
> > to my DSL modem back when, and it's what connects to the Hughesnet
> > device now.
> >
> >
>
> First, are you absolutely certain the router is not using NAT?
Nope.
> I would expect an Internet router to do so by default. Many routers can disable NAT, 'bridge mode', but then you need all IP addresses to
> be on the same subnet and it isn't a router at all. Almost certainly, if the router has a port forwarding feature that is not disabled, there is
> NAT working.
>
> What can you ping from where?
Ah, that's where it got "interesting" this morning...
> Are you able to turn off the firewall function of the router for testing? If you ever see ping work in one
> direction but not the other between the same two hosts, it's NAT/firewall trouble.
Noted.
> The modem itself will probably have a 'ping' option,
I don't see one in there. I log into it in my browser and the whole UI is graphical, with menus and such.
> I assume it can ping 192.169.1.2 successfully, can it ping the server? It would be nice
> if it had a traceroute facility, but they usually don't.
Nope.
> What about ping and traceroute from a wifi client? What do you get if
> you try to trace a route to the server?
Phone and tablet are both android, which tends to not provide that kind of tools. I have some laptops here I could probably get going and maybe use one of them to test this out.
I came in here this morning and this email client seemed to be stuck, and a bit of poking at it got me some "unknown host" errors. Huh? I couldn't ping *anything* from this machine, though the lady of the house didn't seem to be having any trouble from her machine. I did try and hit the server from my phone last night, via wifi, and didn't get there, but I saw a faint image that looked like the modem?! Anyway, after seeing those errors this morning I un-did the changes in the modem and now things are working fine. That modem originally wanted to be 192.168.0.1, which is what my server is, and I did change it when the dish setup was installed, but apparently there's a bug somewhere in the firmware where the original address is being retained, or I've got some other bit that I need to fiddle with in there to make this work. I may have a go at contacting their tech support, but so far that doesn't look terribly promising...
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