# [SOLVED] Problem with connection for CIDR /32 network

## dziadu

During my stay in hotel I was trying to get access to public hotel network. After connection to the AP I receive IP address:

```
# ifconfig wlan0

wlan0     Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx  

          inet addr:172.30.2.100  Bcast:172.30.3.255  Mask:255.255.255.255

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:39 errors:0 dropped:0 overruns:0 frame:0

          TX packets:6 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000 

          RX bytes:2635 (2.5 KiB)  TX bytes:706 (706.0 B)
```

But network connection is unavailable (no ping to any server). Route shows:

```
# route

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

loopback        localhost       255.0.0.0       UG    0      0        0 lo
```

Then I tried to connect using Windows Vista Ultimate. After selecting network and successful connecting, I opened web browser, opened page (i.e. google), then special page appear. I had to click to button: "Open ticket for the network connection", and after that I got access to the network. Without any problems.

What is interesting, IP address which I receive under the Windows is 172.30.0.94 (on Linux it is 172.30.2.100), but MAC is the same in both cases.

I've found only one page which concern to the same problem: https://answers.launchpad.net/ubuntu/+question/23845 but it doesn't solve the problem.

Network is built-up on proxy: surfnet.iacboxLast edited by dziadu on Thu Mar 11, 2010 6:51 pm; edited 1 time in total

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## loisl

I have never seen a /32 IP address on a multipoint (like wireless or Ethernet) connection. For me this looks like a misconfiguration or malfunction of Your DHCP client. I am wondering that Your Linux routing table does not show any routes related to Your wireless interface. Even for a /32 IP address it should contain something. This additionally leads to the DHCP client.

For a deeper analysis more information would be helpful:

IP netmask during the Windows session

routing table of the Windows session

Getting different IP addresses for the Windows and for the Linux session is somewhat normal. On public access points You find very often IP address renewals for DHCP in intervals below 5 minutes and when the wireless session disconnects (e.g. because of a reboot) You end up with a totally different IP for the same MAC.

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## dziadu

I am not longer in this hotel, but I checked it several times, and I am sure that on the Windows I got the same values:

- IP address 172.30.0.94/32

- gateway 172.30.3.254

- DNS 172.30.3.254

On the Linux I got:

- IP address 172.30.2.100/32

- gateway - no gateway (no routing table),

- DNS - 172.30.3.254 (from /etc/resolv.conf).

I was running Linux and Windows alternately several times trying to get it running on Linux and looking for info on Windows, and IP addresses were always the same, but different for both.

This strange CIDR /32 in maybe because of this used proxy. Now I have to say I am not network specialists and I don't know nothing about proxies and things like this. I can configure simple network, and never ever before I have such strange problem.

The guy from link from my first post had the same problem, the same IP addresses so I gues he found the same proxy system.

Now I look little bit deeper into google and found this on (from the website of the proxy): http://www.iacbox.com/index.php?id=49&backPID=23&L=1&tx_faq_faq=174

I was trying add route table by hand but it didn't work. Now is to late to check it again.

So I think It (should) solve the problem. Thanks for your advice.

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