Re: Modem/Router/Router -

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Tim:
>> If you could put the ISP supplied thingummy into bridge mode, it
>> would act simply as a modem, giving a bare ethernet output to your
>> own router.

See this diagram:
https://pasteboard.co/Ib7teuG.png

The upper three boxes show what we think your current situation is.

Internal to the ISP's modem/router is drawn in the cloud below.  In
it's modem/router mode, it's a modem followed by a router doing NAT.

NAT means Network Address Translation, which means that it (*any*
router doing NAT) is doing several things:

 * Sharing your single connection to the internet to all your LAN
   devices.
 * Giving each device on your LAN its own different IP address
   (different from the WAN address your ISP is allocating to you, and
   each device has a unique address).  It's using its own DHCP server
   to allocate these addresses.
 * Managing routing the right connections between inside devices and
   the outside world (so that a LAN computer browsing the web, gets its
   results directed to it, and other LAN computers get their own
   traffic).

The ISP's router's (router 1 on my drawing) WAN input is being assigned
an IP to its router input from upstream (the ISP's DHCP server is
giving it this IP).  This will be your public IP that the whole world
sees you as.

That router (1) will be using its own DHCP server to assign addresses
to the devices connected to its output (in your case, that's just your
own router (2) directly connected to it), and router 1 will self assign
an IP to itself for the LAN side of its connections (often a .254
suffixed numerical IP address).  These will usually be private IPs in a
192.168.x.y range (there are other ranges).  For the sake of my
diagram, I'm using 192.168.1.y as the range the first router (in the
middle) is doling out.  The router will probably assign itself
192.168.1.254, and then the first device it gives an IP to will
probably be assigned 192.168.1.1

Your own router (2) is being assigned an IP from the first router (1),
it's probably be 192.168.1.1.  That will be its WAN IP (what something
coming from the WAN side of it will address it as).  Your own router
will assign itself a different LAN IP (again, probably one ending with
.254), and it will also assign IPs to devices coming after it on your
LAN.  However, to avoid a networking nightmare, it's *virtually*
essential to configure your router to use a different subnet.  In my
diagram, I've shown the second router using the 192.168.2.y subnet
range.  The router would be calling itself 192.168.2.254, and all your
LAN devices would see it at that address.  The router will be doling
out IPs like 192.168.2.1 to the devices connected to its LAN side.

	(They don't have to be those particular subnet
	 numbers, I've just chosen obvious ones to suit
	 the example.  And it *may* be possible that you
	 could get away with everything being on the
	 same subnet, but you'd be relying on both
	 routers coping with this, and they may not
	 be able to.)

If you let your LAN computers be automatically configured, this would
normally work things out by themselves, fine.  But if you manually
configure devices, then they must use an IP within the range the router
is going to accept (they must be the same subnet), but shouldn't be
using an IP that the router might automatically dole out.

e.g. Your second router would be using 192.168.2.1 to 192.168.2.253 as
LAN IPs.  Its DHCP server might automatically dole out a narrower IPs
from 192.168.2.1 through to 192.168.2.100, leaving you to use IPs from
192.168.2.101 through to 192.168.2.253 on devices that you will
manually configure.

Now, because of all this convolutedness (of two daisy-chained routers),
to get things working, it may well be essential that you first get the
satellite system up, then power up the ISP's modem/router and let it
fully finish booting before you power up your own router.  The ISP's
modem/router has to assign your router an IP.  It won't do that until
it's finished booting up.  And your router may give up waiting before
it gets assigned an IP, and not make any further attempts to get one.

If you could put the modem/router into bridge mode, then that bypasses
its router.  You'd get the direct output from the modem, using your
public IP, going into the input of your router.  And, you can see from
my diagram, why it gets called a bridge connection (it goes over the
router, and completely bypasses it).

Other things to note:

Because there's at least one level of NAT between your ISP and your
computers, if your ISP changes your IP on you, none of your internal
IPs change.  Your router(s) are managing that, not the ISP.

Normally your routers would keep assigning your own computers the same
IP each time.  You can (usually) configure them to make sure that they
do (enter the computer's MAC address into the router's DHCP config).

To configure the first router, you may need to connect a computer
directly to its output, it may not allow configuration from an IP
outside its subnet.

If you connect the second router LAN side to the first router, leaving
the WAN port disconnected, then the second router is just acting as a
switch, and you could have two DHCP servers (one from each router)
fighting with each other.

Having two daisy chained routers can work, but you need to make sure
that the LAN addressing is managed well.  You'd have to manage your
second router's WiFi (use a different SSID, passphrase, and channel).

Bob Goodwin (re bridge mode):
> I have found nothing in the settings indicating that option is 
> available.

It's probably in there, but your ISP could have rejigged the modem to
remove all manner of configuration options from you.

> NetworkManager shows two connection options, Ethernet (eno1)  
> virbr0, I have it running at the eno1 and a fixed ipaddress on this 
> computer, that works, the other never did where it would like to be 
> 192.168.122.1. My router does not normally work with that subnet?

It probably doesn't.  And that's more NATing inside your computer, to
virtual computing running inside your computer (computers inside
computers, Russian doll style).

> The same modem-router is available as new it appears on eBay. I
> assume it would not have any other features ...

It could have still features that your ISP has removed.

> It is labeled Viasat and model RG1100, the manual is barely
> adequate, written in several languages interspersed by paragraph,
> annoying but I read through it several times to glean what I could
> from it.

Sometimes it's worth looking for an online manual, it may have been
updated, or repaginated.

>> It may be worth contacting your ISP and forthrightly mentioning
>> that the replacement model is inadequate for your needs, mentioning
>> those two particular 

> I have phoned the ISP numerous times, each call is an adventure, all
> I get is gibberish in very hard to understand English. I was married
> to a French woman for 45 years ad do not require perfect spoken
> English but in too many cases support is a joke in my opinion.

See if you can find a technical support email address.  You might get
the issue looked at someone who actually is a tech, rather than someone
just reading (something that they don't understand) from the usual
user-support scripts.

You may find one of their answers is to upgrade to a more expensive
service, with a bigger download limit.

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