Results 1 to 7 of 7

Thread: Airbase working, but dhcpd is not

Threaded View

  1. #1
    Just burned his ISO
    Join Date
    Jun 2010

    Default Airbase working, but dhcpd is not

    I have been trying to configure bt4r1 to use airbase along with dhcp. However, while the clients are able to connect, they never get ip addresses. The following is, from start to finish, my process. Note that I have replaced (consistently) all the MAC addresses with fakes. I'm a bit of a paranoid loony.

    I insert my usb wireless card (Alfa AWUS036H), check dmesg to make sure everything went well.
    usb 1-4: new high speed USB device using ehci_hcd and address 4
    phy1: Selected rate control algorithm 'minstrel'
    phy1: hwaddr 00:c0:ca:3e:f3:eb, RTL8187vB (default) V1 + rtl8225z2, rfkill mask 2
    rtl8187: Customer ID is 0xFF
    Registered led device: rtl8187-phy1::radio
    Registered led device: rtl8187-phy1::tx
    Registered led device: rtl8187-phy1::rx
    rtl8187: wireless switch is on
    usbcore: registered new interface driver rtl8187
    All looking good, I put it into monitor mode.
    root@bt:~# airmon-ng check
    root@bt:~# airmon-ng start wlan1
    Interface  Chipset   	   Driver
    wlan0	   		   Intel 3945ABG	iwl3945 - [phy0]
    wlan1			   	 RTL8187 	rtl8187 - [phy1]
    				 			  (monitor mode enabled on mon
    I now check to make sure my wireless card is up to snuff.
    root@bt:~# aireplay-ng --test mon0
    12:10:05  Trying broadcast probe requests...
    12:10:05  Injection is working!
    12:10:07  Found 2 APs
    12:10:07  Trying directed probe requests...
    12:10:07  C0:3F:0E:B5:03:5E - channel: 1 - 'redacted1'
    12:10:08  Ping (min/avg/max): 3.401ms/26.161ms/44.078ms Power: -61.14
    12:10:08  29/30:  96%
    12:10:08  00:25:9C:D1:19:6A - channel: 1 - 'redacted2'
    12:10:09  Ping (min/avg/max): 2.738ms/14.681ms/39.091ms Power: -66.52
    12:10:09  23/30:  76%
    I start airbase. I want the channel to be '5', the essid to be 'A trap', and some debugging info. I run this on the monitor mode enabled interface I created with airmon.
    root@bt:~# airbase-ng -c 5 -e 'A trap' -v mon0 
    12:15:03  Created tap interface at0
    12:15:03  Trying to set MTU on at0 to 1500
    12:15:03  Trying to set MTU on mon0 to 1800
    12:15:03  Access Point with BSSID 00:C0:CA:3E:F3:EB started.
    I grab my 802.11 enabled phone, switch on wireless, and connect
    12:15:54  Got an auth request from 38:E7:D8:A7:C7:59 (open system)
    12:15:54  Client 38:E7:D8:A7:C7:59 associated (unencrypted) to ESSID: "A trap"
    Great! Works so far. Now I want to configure a DHCP server.

    I want the network to be (netmask:, gateway/AP (at0) to be, and ip address leases to span

    I configure at0 to match this scheme.
    root@bt:~# ifconfig at0 up ip netmask
    root@bt:~# ifconfig at0
    at0       Link encap:Ethernet  HWaddr 00:c0:ca:3e:f3:eb  
              inet addr:  Bcast:  Mask:
              inet6 addr: fe80::2c0:caff:fe3e:f3eb/64 Scope:Link
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:52 errors:0 dropped:0 overruns:0 frame:0
              TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:500 
              RX bytes:13364 (13.3 KB)  TX bytes:328 (328.0 B)
    And then edit /etc/dhcp3/dhcpd.conf
    ddns-update-style none;
    # I had no idea what I should put for this so I settled on "home"
    option domain-name "home";
    # OpenDNS servers found in
    option domain-name-servers,;
    default-lease-time 600;
    max-lease-time 7200;
    # If this DHCP server is the official DHCP server for the local
    # network, the authoritative directive should be uncommented.
    # Use this to send dhcp log messages to a different log file (you also
    # have to hack syslog.conf to complete the redirection).
    log-facility local7;
    subnet netmask {
    Now, with crossed fingers, I start the dhcp server
    root@bt:~# touch /var/run/
    root@bt:~# chown dhcpd:dhcpd /var/run/
    root@bt:~# dhcpd3 -d at0
    Internet Systems Consortium DHCP Server V3.1.1
    Copyright 2004-2008 Internet Systems Consortium.
    All rights reserved.
    For info, please visit
    Wrote 0 leases to leases file.
    Listening on LPF/at0/00:c0:ca:3e:f3:eb/192.168.2/24
    Sending on   LPF/at0/00:c0:ca:3e:f3:eb/192.168.2/24
    Sending on   Socket/fallback/fallback-net
    And once again I try to connect my phone..
    12:36:12  Got an auth request from 38:E7:D8:A7:C7:59 (open system)
    12:36:12  Client 38:E7:D8:A7:C7:59 associated (unencrypted) to ESSID: "A trap"
    But dhcpd3 stays quiet and, after trying to obtain an ip address for awhile and failing, my phone gives up.

    How come?

    Thank you for reading,
    Max Carini
    Last edited by chaohacker; 08-28-2010 at 02:09 AM. Reason: adding info

Similar Threads

  1. Replies: 0
    Last Post: 05-10-2010, 12:48 PM
  2. No IP from dhcpd with softAP/Airbase-ng
    By fiuvertiz in forum OLD BackTrack 4 Software Related Issues
    Replies: 4
    Last Post: 03-10-2010, 08:42 AM
  3. DHCPD config help
    By Revelati in forum OLD Newbie Area
    Replies: 3
    Last Post: 10-11-2008, 11:07 PM
  4. dhcpd
    By hhmatt in forum OLD BT3beta General
    Replies: 6
    Last Post: 03-05-2008, 05:15 AM
  5. Dhcpd in BT2?
    By pjmcgarvey in forum OLD BackTrack v2.0 Final
    Replies: 2
    Last Post: 05-18-2007, 08:13 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts