[PLUG-TALK] Wireless in Munchkinland

[Bill Barry]

On Thu, Aug 30, 2012 at 7:56 AM, Keith Lofstrom <keithl at gate.kl-ic.com> wrote:
> I'm looking for some wireless kludge setup advice.
>
> I spent a couple of hours waiting for my next flight at Kansas
> City airport, aka MCI, aka MunChkInland airport because the
> divided-down-the-spine terminal is too small for large-sized
> adults.  Kansas City is in Missouri, so when Dorothy's house
> flew in, "not in Kansas anymore", this is where it landed.
> AFAIK, our 737 did not crush any witches, so air traffic
> control seems to be functioning somewhat better these days.
>
> I had hoped to use the alleged free wireless, but the setup is
> strange - it seems that the gateway is not within the assigned
> address range.  Here are some lines from /var/log/messages:
>
> Aug 29 14:28:25 kao NetworkManager: <info>    address 10.203.63.150
> Aug 29 14:28:25 kao NetworkManager: <info>    prefix 22 (255.255.252.0)
> Aug 29 14:28:25 kao NetworkManager: <info>    gateway 74.5.120.9
> Aug 29 14:28:25 kao NetworkManager: <info>    nameserver '204.117.214.10'
> Aug 29 14:28:25 kao NetworkManager: <info>    nameserver '199.2.252.10'
>
> Note that the gateway (74.5.120.9) is not within the segment
> address range assigned by the WAP:  10.203.60:xx to 10.203.63.xx
> and I kept getting "no route to" error messages when I tried to
> connect anywhere.   I even tried (horrors!) turning off iptables
> to see if that was blocking something that Linux does when faced
> with this misconfiguration.  Perhaps Windoze (and newer Linux
> distros) have some hack to bypass this WAP misconfiguration, so
> most people get connected.
>
> My ifconfig/route knowledge was not adequate for the task, the
> terse man pages did not contain suggestions for dealing with idiotic
> WAP configs, and of course google was not available to educate me.
>
> Where I am now, it works:
>
> Aug 30 07:10:43 kao NetworkManager: <info>    address 192.168.2.2
> Aug 30 07:10:43 kao NetworkManager: <info>    prefix 24 (255.255.255.0)
> Aug 30 07:10:43 kao NetworkManager: <info>    gateway 192.168.2.1
> Aug 30 07:10:43 kao NetworkManager: <info>    nameserver '192.168.2.1'
> Aug 30 07:10:43 kao NetworkManager: <info>    domain name 'chphelps'
>
> route -n:
>
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
> 192.168.2.0     0.0.0.0         255.255.255.0   U     2      0        0 wlan1
> 0.0.0.0         192.168.2.1     0.0.0.0         UG    0      0        0 wlan1
>
> ----------------------------------------
>
> So, if I ever find myself in Kansas City again, hubbing and
> hobnobbing with the hobbits, I imagine I must type in some
> manual connection commands after NetworkManager fails.
>
> Suggestions?
>
> Keith
>

As you have diagnosed, the gateway is not in the subnet where your ip
address is. This is perfectly legal to do. The problem is that the
dhcp client is not handling that situation correctly. The work around
as suggested here

https://bbs.archlinux.org/viewtopic.php?id=72685  is to add a route to
the gateway

route add 74.5.120.9/32 dev wlan1

I had a similar problem with a /32 network in the Benton County
Library several years ago, so I know that the place to report such
bugs for the ISC dhcp client  is dhcp-bugs at isc.org

Bill