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Date:      Fri, 15 Jun 2018 23:37:07 +0200
From:      Polytropon <freebsd@edvax.de>
To:        B J <va6bmj@gmail.com>
Cc:        freebsd@dreamchaser.org, Chris Gordon <freebsd@theory14.net>, freebsd-questions <freebsd-questions@freebsd.org>, Erich Dollansky <freebsd.ed.lists@sumeritec.com>
Subject:   Re: Problems Connecting Laptop To Modem
Message-ID:  <20180615233707.8645c246.freebsd@edvax.de>
In-Reply-To: <CAP7QzkPg%2BmQCEePf_DVZCuwybL3MLcNXAgfp1yRETk0qR50BhA@mail.gmail.com>
References:  <CAP7QzkM7QnymxoOz_ZEUebaOMcE%2BwWmpv7sz6-SzjC0BHG6LCA@mail.gmail.com> <20180613102426.3874c581.freebsd.ed.lists@sumeritec.com> <CAP7QzkM0FdUMwtG3TDtW11T-ZTQ8QC2p6qHWn2BjEjPC8jXG9w@mail.gmail.com> <20180613162137.5cc6794a.freebsd.ed.lists@sumeritec.com> <CAP7QzkOzK=7u5Vf0FLdiz6f1%2BSbhme3RpF9MpYUoAJLqTH15qw@mail.gmail.com> <3E3890A6-72F9-4D80-A021-837FFDB35A39@theory14.net> <CAP7QzkNK2qfAL=2-og5oyAY9KLuYVXCfbZ_akbWoEP-xwCP%2BJw@mail.gmail.com> <20180614093928.6f39434e.freebsd.ed.lists@sumeritec.com> <CAP7QzkN6jtukm-ieWEaPsuo6bCTJh0xLdJYOdALVUs6fgSJtwg@mail.gmail.com> <20180614161923.5246ae81.freebsd.ed.lists@sumeritec.com> <CAP7QzkPL5732dh3%2BVmbT6mXxkiYGjUOgiHvUwWBJRk2VJK-y2w@mail.gmail.com> <20180615102548.1c686d1b.freebsd.ed.lists@sumeritec.com> <CAP7QzkODpMCy1TNRpC_-oVmatXE7V1h%2BZEds1R%2B2UCFCu76C%2BA@mail.gmail.com> <ef7f1a05-68c7-c787-5d73-c9848e30acf3@dreamchaser.org> <CAP7QzkPg%2BmQCEePf_DVZCuwybL3MLcNXAgfp1yRETk0qR50BhA@mail.gmail.com>

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On Fri, 15 Jun 2018 20:49:12 +0000, B J wrote:
> On 6/15/18, Gary Aitken <freebsd@dreamchaser.org> wrote:
> 
> <snip>
> 
> > You can't just add the default router line without a bit of knowledge
> > about what the IP address of the default router actually is.  Do you
> > know what the 192.168.0.* address for the router is?  I suggested
> > 192.168.0.1 because that is often the default, but not necessarily so.
> 
> I eventually found that 192.168.0.1 was the value from one of my tower
> machines.  I tried other values for the last number as well and got
> the same result.

>From your netstat output (later on), it seems that you
connect to 192.168.0.1, so if this really is the IP of
one of your machines, there's a big problem with your
current configuration.



> >> That might be worth considering, but I don't have to do it with my
> >> other FreeBSD machines.
> >
> > Can you post the result of "netstat -rn" from one of those other
> > machines?
> 
> <snip>
> 
> Routing tables
> 
> Internet:
> Destination        Gateway            Flags     Netif Expire
> default            192.168.0.1        UGS        fxp0
> 127.0.0.1          link#2             UH          lo0
> 192.168.0.0/24     link#1             U          fxp0
> 192.168.0.12       link#1             UHS         lo0
> 
> Internet6:
> Destination                       Gateway                       Flags
>    Netif Expire
> ::/96                             ::1                           UGRS        lo0
> ::1                               link#2                        UH          lo0
> ::ffff:0.0.0.0/96                 ::1                           UGRS        lo0
> fe80::/10                         ::1                           UGRS        lo0
> fe80::%fxp0/64                    link#1                        U          fxp0
> fe80::21a:92ff:fe10:ce8b%fxp0     link#1                        UHS         lo0
> fe80::%lo0/64                     link#2                        U           lo0
> fe80::1%lo0                       link#2                        UHS         lo0
> ff02::/16                         ::1                           UGRS        lo0
> 
> I've had no problem with the machine where this came from.  I just
> checked the laptop using a live version of Ubuntu and I was able to
> connect to the Internet with it.  The hardware, it would seem, doesn't
> appear to be the main problem.

At the moment, it doesn't look like a hardware issue.

My suggestion:

Take a machine that properly connects to your modem/router and
gains Internet access this way as desired. Collect information
about which values exist on your network. Don't guess values. :-)

The following commands should work on FreeBSD and Linux:

	# arp -a

	# netstat -rn

	# ifconfig -a

(depending on Linux, the "ip" program has to be used instead)

Even though it might sound stupid, use pen & paper to make a
small diagram of your network. Write down the IPs and other
elements of the configuration.

If you have a Linux live system connecting without any further
configuration, it's quite possible you have a DHCP server in
your modem/router running. In that case, don't try to configure
things manually, it will just interfere with this mechanism.
Instead, use

	ifconfig_nfe0="DHCP"

in /etc/rc.conf. A variation is

	ifconfig_nfe0="SYNCDHCP"

Check /etc/rc.conf for duplicate entries. The _last_ entry
of the same kind will be in effect, as it's basically just
a shell script with assignments to shell variables.

Of course you need to specify the default router address, but
don't guess it - determine it from a different system. If it
is the _default_ address that your modem/router uses (and you
didn't change it), maybe consult its documentation, the address
should be listed there. It can be things like 192.168.0.1, 
192.168.1.1, 192.168.178.1, who knows.

Check if HDCP populated /etc/resolv.conf. In many settings,
the modem/router will also be a nameserver (even if it just
"relays" your queries and the replies). This means: The IP
you're seeing there is the IP of your modem/router.

In worst case, don't configure anything in /etc/rc.conf and do
a little experimentation. Run a tcpdump (or maybe Wireshark,
ex Ethereal) on your network interface and then do all the steps
manually: Configure the interface, set default routing, try to
obtain an IP via DHCP (using dhclient), and see it /etc/resolv.conf
gets populated (which DHCP should fill with the correct values).
Then try to ping internally with IP, extermally with IP, try to
resolve a hostname, ping it, open a browser for a HTTP connection,
and so on. Monitor what you're doing as initially mentioned (to
see if you actually _see_ what you expect, like ARP messages,
a DHCP handshake, ICMP pings, and HTTP traffic). If this all
works, make the settings permanent - even if you only verified
that using DHCP was the correct thing to begin with. :-)

Good luck!




PS.
"Trial & error" is not a programming concept. ;-)


-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...



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