（一）、通過Xmodem命令（注：Xmodem與實際的modem沒有任何聯系，只是一個傳輸協議，transfer moder,因為transfer常被縮
寫為xfer, 數據是通過終端的串口和路由器的的Console口灌進去的）升級IOS，具體步驟如下：
1、用Cisco原配的線纜連接路由器的console口與PC機的COM1，使用PC機的超級終端軟件訪問路由器，這時不需要對PC和路由器配置任
何地址。
2、在這個模式下，輸入Xmodem命令，即：
QUOTE:
rommon 2 > xmodem -c c2600-i-mz.122-11.bin （-c是帶校驗，c2600-i-mz.122-11.bin為存放在PC機上的IOS映像文件）
WARNING: All existing data in bootflash will be lost!
Invoke this application only for disaster recovery.
Do you wish to continue? y/n [n]: y
Ready to receive file c2600-i-mz.122-11.bin ...
（此時在超級終端的傳送欄目=> 選擇發送文件選項 => 再選擇Xmodem 並指明IOS映像文件所在的路徑，按發送即開始上傳IOS,等待時
間很長，視IOS的大小和傳輸速度。）
QUOTE:
Erasing flash at 0x607c0000
program flash location 0x605b0000
Download Complete!
傳完以後，對整個系統初始化 顯示如下：
QUOTE:
program load complete, entry point: 0x80008000, size: 0x5b85e0
Self decompressing the image : #################################################
################################################# [OK]
Smart Init is disabled. IOMEM set to: 10
Using iomem percentage: 10
Restricted Rights Legend
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.
cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134-1706
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-I-M), Version 12.2(11)T9, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Mon 23-Jun-03 15:42 by cmong
Image text-base: 0x8000809C, data-base: 0x80A68B48
cisco 2610 (MPC860) processor (revision 0x203) with 22528K/2048K bytes of memory
Processor board ID JAD03483395 (1128032249)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
1 Ethernet/IEEE 802.3 interface(s)
2 Serial(sync/async) network interface(s)
32K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)
Press RETURN to get started!
*Mar 1 00:00:05.652: %PA-2-UNDEFPA: Undefined Port Adaptor type 100 in bay 1
*Mar 1 00:00:07.996: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to up
*Mar 1 00:00:07.996: %LINK-3-UPDOWN: Interface Serial0/0, changed state to down
*Mar 1 00:00:07.996: %LINK-3-UPDOWN: Interface Serial0/1, changed state to down
*Mar 1 00:00:09.142: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0, changed state to up
*Mar 1 00:00:09.142: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to down
*Mar 1 00:00:09.142: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/1, changed state to down
*Mar 1 00:00:09.458: %SYS-5-CONFIG_I: Configured from memory by console
*Mar 1 00:00:11.245: %LINK-5-CHANGED: Interface Serial0/1, changed state to administratively down
*Mar 1 00:00:12.275: %SYS-5-RESTART: System restarted --Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-I-M), Version 12.2(11)T9, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Mon 23-Jun-03 15:42 by cmong
*Mar 1 00:00:12.279: %SNMP-5-COLDSTART: SNMP agent on host NE16 is undergoing a cold start
Router>
采用這種方法時，由於使用console口來傳送，速率為9600bps，需要時間較長。因此可修改console口速率利用xmodem命令實現快速升級IOS。具體方法如下：
QUOTE:
rommon 1 > confreg
Configuration Summary
enabled are:
load rom after netboot fails
console baud: 9600
boot: image specified by the boot system commands
or default to: cisco2-C2600
do you wish to change the configuration? y/n [n]: y (選擇 yes)
enable "diagnostic mode"? y/n [n]: n (選擇 no)
enable "use net in IP bcast address"? y/n [n]: n (選擇 no)
disable "load rom after netboot fails"? y/n [n]: n (選擇 no)
enable "use all zero broadcast"? y/n [n]: n (選擇 no)
enable "break/abort has effect"? y/n [n]: n (選擇 no)
enable "ignore system config info"? y/n [n]: n (選擇 no)
change console baud rate? y/n [n]: y (選擇 yes)
enter rate: 0 = 9600, 1 = 4800, 2 = 1200, 3 = 2400
4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200 [0]: 7 (選擇 7,用最大的11520
速率的xmodem傳輸)
change the boot characteristics? y/n [n]: n (選擇 no)
Configuration Summary
enabled are:
load rom after netboot fails
console baud: 115200
boot: image specified by the boot system commands
or default to: cisco2-C2600
do you wish to change the configuration? y/n [n]: n (選擇 no)
You must reset or power cycle for new config to take effect
rommon 2 > reset
注意：在按reset鍵前，需要修改串口速度（我的電腦---端口屬性----串口速度調為 115200），然後再修改超級終端裡設置速率為115200，記住，一定要這麼做，否則會出現亂碼！然後關閉這個超級終端，重新建立一個超級終端連接，重新啟動系統後，出現
QUOTE:
rommon 1>
然後,輸入