Configuring a 3602 for Wireless Surveying

Cisco has recently released their new flagship access point, the 3602. This access point is nothing short of a beast. It has been completely redesigned with 4 transmit and 4 receive antennas and can sustain three spatial streams. This AP also features the first-to-market expansion slot that will be used for the Security and Spectrum Intelligence (SSI) module scheduled for release in Q1 of 2013. Cisco will then be releasing an 802.11ac capable module in the first half of 2013.

Now that you’ve invested (or are planning on investing) in this new generation of access points, you’re going to be out surveying new deployments with them. The only problem with this AP is it comes with a Lightweight IOS image preloaded. Cisco does offer a feature limited autonomous IOS that can be used for surveying – which is what we will be setting up and configuring today.

This process will require a few things:

  • Cisco 3600 Autonomous IOS (Available from Cisco.com)
  • TFTP Server (Available free from http://tftpd32.jounin.net)
  • Console Cable
  • Switch – Workstation and AP MUST be on the same VLAN

Below I have listed two options for you to choose from for converting your access point to the autonomous IOS required for active surveying. Option A is your easiest and most preferred method, Option B will work if you run into a problem using Option A.

Option A
Step 1: Change your IP Addressing on your TFTP Server to the following:

  • IP Address: 10.0.0.5

We have to do this because when we set the AP into default mode it will automatically use the address of 10.0.0.2 and will send a broadcast looking for a recovery image.

Step 2: Change the name of your Autonomous IOS to:

  • ap3g2-k9w7-tar.default

Step 3: Boot your AP while holding the MODE button. Do NOT release until you see “image_recovery: Download default IOS tar image tftp://255.255.255.255/ap3g2-k9w7-tar.default.”

At this point you will see the IOS downloading to your AP.

Step 4: Once the download is complete your AP should reboot automatically. If not, then enter the following command to boot into the autonomous IOS.
ap: boot flash:/ap3g2-k9w7-mx.152-2.JA/ap3g2-k9w7-xx.152-2.JA

Now that we have the IOS booted we need to configure the boot statements to make sure we boot into the autonomous IOS at startup.

ap.>enable
Password: Cisco (default password)
ap.#config t
ap.(config)#boot system flash:/ap3g2-k9w7-mx.152-2.JA/ap3g2-k9w7-xx.152-2.JA

Now scroll down to the Configuration section and get ready to survey!

Option B
First things first, load up your TFTP server and set it to use the folder where your IOS is stored.

Now that your TFTP server is ready, we can get your access point ready to go.

My network is addressed as a 192.168.1.0/24 network and this is the addressing we will be using for the remaining commands in this guide.

Step 1: Boot your AP while holding the MODE button. Do NOT release until you see “image_recovery: Download default IOS tar image tftp://255.255.255.255/ap3g2-k9w7-tar.default.”

Step 2: At the ‘ap:’ prompt, configure the following commands:
ap: set IP_ADDR 192.168.1.10
ap: set NETMASK 255.255.255.0
ap: set DEFAULT_ROUTER 192.168.1.1

Step 3: Prepare the AP for the TFTP transmission.
ap: ether_init
ap: tftp_init

Step 4: Using the tar command begin the TFTP transmission.
ap: tar -xtract tftp://(ServerIP)/Filename Flash:
eg: ap: tar -xtract tftp://192.168.1.5/ap3g2-k9w7-tar.152-2.JA.tar flash:

This portion may take some time, but keep an eye on it to make sure there are no prompts that may time the process out.

Step 5: Boot into the new autonomous IOS.
ap: boot flash:/ap3g2-k9w7-mx.152-2.JA/ap3g2-k9w7-xx.152-2.JA

Now that we have the IOS booted we need to configure the boot statements to make sure we boot into the autonomous IOS at startup.

ap.>enable
Password: Cisco
(default password)
ap.#config t
ap.(config)#boot system flash:/ap3g2-k9w7-mx.152-2.JA/ap3g2-k9w7-xx.152-2.JA

SSID Configuration
Finally, we can now begin configuring the AP for surveying.
What I prefer to do is to create an SSID on the 2.4GHz frequency and a separate SSID for the 5GHz frequency. It makes it easier for me while in the field to select the correct band I want to survey. We will step through the process for creating both and some of the options we can use.

Step 1: Let’s create the 5GHz SSID:
ap.#Dot11 SSID Survey-5
ap.(config-ssid)#Authentication Open
ap.(config-ssid)#guest-mode
– This tells the AP to broadcast this SSID.

Step 2: Now let’s configure the 5GHz Radio, Dot11Radio1.
ap.(config)#interface dot11radio1
ap.(config-if)#ssid Survey-5
ap.(config-if)#channel width 40-above
– Set your channel width to what you will be using in production, either 20MHz or 40MHz.
ap.(config-if)#channel 5180 – Locks the AP into using channel 36. This will come in handy when setting up your channel scanning in your surveying program.
ap.(config-if)#power local 17 – this will configure the radio to use 50mW – Refer to Cisco Radio Transmit Power for a handy conversion chart.
ap.(config-if)#no shutdown

At this point you now have the ability to connect to the access point and can survey on 5GHz. Now let’s continue by configuring the 2.4GHz Radio.

Many of the steps will be the same, with minor differences.

Step 1: Let’s create the 2.4GHz SSID:
ap.#Dot11 SSID Survey-2
ap.(config-ssid)#Authentication Open
ap.(config-ssid)#guest-mode
– This tells the AP to broadcast this SSID

Step 2: Now let’s configure the 2.4GHz Radio, Dot11Radio0.
ap.(config)#interface dot11radio0
ap.(config-if)#ssid Survey-2
ap.(config-if)#channel width 20
– This is the default and does not need to be entered, I just wanted you to know that 20MHz is the only option for 2.4GHz.
ap.(config-if)#channel 1 – Locks the AP into using channel 1. This will come in handy when setting up your channel scanning in your surveying program.
ap.(config-if)#power local 14 – This will configure the radio to use 25mW – Refer to Cisco Radio Transmit Power for a handy conversion chart.
ap.(config-if)#no shutdown

DHCP Configuration
You can enable your AP to be a DHCP server – allowing for quicker configuration changes in the field.
ap.(config)#interface BVI 1
ap.(config-if)#ip address 192.168.0.1 255.255.255.0
ap.(config-if)#exit
ap.(config)#ip dhcp excluded-address 192.168.0.1 192.168.0.5
ap.(config)#ip dhcp pool NAME
ap.(dhcp-config)#network 192.168.0.0 /24
ap.(dhcp-config)#default-router 192.168.0.1

You can now telnet into your AP using the default username Cisco and password Cisco.

Well, that’s it! You’re done and ready to go out into the wild blue yonder and survey to your hearts content!
In the next blog we will be using the SSIDs that we just created to perform surveys using Airmagnet Pro.
Please leave any feedback in the comments and feel free to ask questions.

Credit for the steps to TFTP the IOS goto Vinay Sharma