原本想采用官方推荐的方法进行升级，不过感觉不怎么方便。官方的升级方法地址如下：

http://www.cisco.com/en/US/docs/wireless/access_point/conversion/lwapp/upgrade/guide/lwapnote.html

麻烦之处有几点：1.每台胖AP都必须登录后配置用户密码、启动TELNET、配置接口地址等信息；2.虽然软件可以一次同时升级6台设备，但前提是你有一定的网络环境才可以；……

由于以上的几点，我采用了另外的一种方法进行胖AP升级到瘦AP。以下是整个升级过程：

准备工作：

1.Cisco TFTP Server程序并配置电脑IP为：10.0.0.2/255.0.0.0

2.准备瘦AP的IOS文件：如c1240-k9w7-tar.default；下载位置：

http://www.cisco.com/public/sw-center/index.shtml

操作过程：

按住AP上的MODEL按钮， 接通AP电源， 不要松开MODEL键，直至指示灯变为蓝色、×××到粉色，在启动的过程中你会看到AP有一个默认IP地址为10.0.0.1, 而且会发送广播（发向255.255.255.255）寻找TFTP服务器，试图从TFTP服务器下载相对应的IOS（搜索与AP上默认文件名相同名称的文件，注意看AP上的信息，类似于“c1140-k9w7-tar.default”），

方法二： 用console线连接到AP上，启动后，能进入config terminal模式的就是胖AP，不能进去(也就是不可配置)的就是瘦AP。

AP升级日志：

Initializing ethernet port 0...

Reset ethernet port 0...

Reset done!

ethernet link up, 100 mbps, full-duplex

Ethernet port 0 initialized: link is up

button is pressed, wait for button to be released...

出现以下信息表示正在升级

process_config_recovery: set IP address and config to default 10.0.0.1

process_config_recovery: p_w_picpath recovery

p_w_picpath_recovery: Download default IOS tar p_w_picpath tftp://255.255.255.255/c1240-k9w7-tar.default

examining p_w_picpath...

extracting info (273 bytes)

Image info:

Version Suffix: rcvk9w8-

Image Name: c1240-rcvk9w8-mx

Version Directory: c1240-rcvk9w8-mx

Ios Image Size: 2632192

Total Image Size: 2632192

Image Feature: WIRELESS LAN|LWAPP|RECOVERY

Image Family: C1240

Wireless Switch Management Version: 3.0.51.0

Extracting files...

c1240-rcvk9w8-mx/ (directory) 0 (bytes)

extracting c1240-rcvk9w8-mx/c1240-rcvk9w8-mx (2622783 bytes)....................

................................................................................

................................................................................

................................................................................

................................................................................

................................................................................

................................................................................

.....................................................................

extracting c1240-rcvk9w8-mx/info (273 bytes)

extracting info.ver (273 bytes)

Deleting current version: flash:/c1240-k9w7-mx.124-3g.JA1...done.

New software p_w_picpath installed in flash:/c1240-rcvk9w8-mx

Configuring system to use new p_w_picpath...done.

Requested system reload in progress...download took about 108 seconds

Loading "flash:/c1240-rcvk9w8-mx/c1240-rcvk9w8-mx"...###########################

################################################################################

################################################################################

######################################################################

File "flash:/c1240-rcvk9w8-mx/c1240-rcvk9w8-mx" uncompressed and installed, entr

y point: 0x3000

executing...

按住MODE键，再插入电源开机。

出现button is pressed, wait for button to be released...时松开MODE键，貌似还要不停的敲回车，才能进 set command 模式，要不然会examining p_w_picpath...。

在出现AP：后，使用set IP_ADDR 10.0.0.1（设IP地址），set NETMASK 255.255.255.0（设掩码），tftp_init （格式化）。

在使用上述命令后，再使用TFTP从电脑上把文件拷下来，命令：tar -xtract tftp://10.0.0.2/c1240-k9w7-tar.124-10b.JA3.tar flash:

下载文件成功后，AP会自动安装。

安装完成后，输入boot重启AP。

Note Your wireless device configuration is not changed when using the CLI to reload the p_w_picpath file.

STEP 1:  Open the CLI using a connection to the wireless device console port.

STEP 2:  Reboot the wireless device by removing power and reapplying power.

STEP 3:  Let the wireless device boot until it begins to inflate the p_w_picpath. When you see these lines on the CLI, press Esc:
Loading "flash:/c350-k9w7-mx.v122_13_ja.20031010/c350-k9w7-mx.v122_13_ja.20031010"
...###########################################################################
################################################################################
################################################################################
####################
STEP 4: When the ap: command prompt appears, enter the set command to assign an IP address, subnet mask,
and default gateway to the wireless device.

Note You must use upper-case characters when you enter the IP-ADDR, NETMASK, and DEFAULT_ROUTER options with the set command.
Your entries might look like this example:
ap: set IP_ADDR 192.168.133.160
ap: set NETMASK 255.255.255.0
ap: set DEFAULT_ROUTER 192.168.133.1

STEP 5: Enter the tftp_init command to prepare the wireless device for TFTP.
ap: tftp_init

STEP 6: Enter the tar command to load and inflate the new p_w_picpath from your TFTP server. The command must include this information:
? the -xtract option, which inflates the p_w_picpath when it is loaded
? the IP address of your TFTP server
? the directory on the TFTP server that contains the p_w_picpath
? the name of the p_w_picpath
? the destination for the p_w_picpath (the wireless device Flash)

Your entry might look like this example:
ap: tar -xtract tftp://192.168.130.222/p_w_picpaths/c350-k9w7-tar.122-13.JA1.tar flash:

STEP 7: When the display becomes full, the CLI pauses and displays --MORE--. Press the spacebar to continue.
extracting info (229 bytes)
c350-k9w7-mx.122-13.JA1/ (directory) 0 (bytes)
c350-k9w7-mx.122-13.JA1/html/ (directory) 0 (bytes)
c350-k9w7-mx.122-13.JA1/html/level1/ (directory) 0 (bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/appsui.js (558 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/back.htm (205 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/cookies.js (5027 bytes).
extracting c350-k9w7-mx.122-13.JA1/html/level1/forms.js (15704 bytes)...
extracting c350-k9w7-mx.122-13.JA1/html/level1/sitewide.js (14621 bytes)...
extracting c350-k9w7-mx.122-13.JA1/html/level1/config.js (2554 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/stylesheet.css (3215 bytes)
c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/ (directory) 0 (bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/ap_title_appname.gif (1422 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_1st.gif (1171 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_cbottom.gif (318 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_current.gif (348 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_last.gif (386 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_last_filler.gif (327 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_last_flat.gif (318 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_button_nth.gif (1177 bytes)
extracting c350-k9w7-mx.122-13.JA1/html/level1/p_w_picpaths/apps_leftnav_dkgreen.gif (869 bytes)
-- MORE --

Note If you do not press the spacebar to continue, the process eventually times out and the wireless device stops inflating the p_w_picpath.

STEP 8: Enter the set BOOT command to designate the new p_w_picpath as the p_w_picpath that the wireless device uses when it reboots. The wireless device creates a directory for the p_w_picpath that has the same name as the p_w_picpath, and you must include the directory in the command. Your entry might look like this example:
ap: set BOOT flash:/c350-k9w7-mx.122-13.JA1/c350-k9w7-mx.122-13.JA1

STEP 9:  Enter the set command to check your bootloader entries.
ap: set
BOOT=flash:/c350-k9w7-mx.122-13.JA1/c350-k9w7-mx.122-13.JA1
DEFAULT_ROUTER=192.168.133.1
IP_ADDR=192.168.133.160
NETMASK=255.255.255.0

STEP 10: Enter the boot command to reboot the wireless device. When the wireless device reboots, it loads the new p_w_picpath.
ap: boot