Recover a Catalyst 9800 controller or the password from ROMMON mode

Introduction

This document describes how to recover a Catalyst 9800 controller based from ROMMON mode and no image in the flash.

Prerequisites

Requirements

Cisco recommends that you have knowledge of these topics:

• Catalyst Wireless Controllers 9800

Components Used

The information in this document is based on these software and hardware versions:

• Catalyst 9800 v16.10.1

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Configure

Password Recovery Procedure for Virtual 9800 (9800-CL)

Step 1. Reboot the 9800-CL. You should quickly see a boot selection screen

Step 2. press 'c' on this screen to get the grub prompt

Step 3. You can change the config register in that prompt with the "confreg 0x2142." command

Step 4. Press the 'esc' key to return to the boot selection prompt and chose the "packages.conf" to boot on the regular image.

Step 5. Your WLC will boot without configuration. Recover it

Step 6. Do not forget to repeat the Procedure from step 1 and to set the config register back to the original value of 0x2002 so that the configuration gets saved and loaded upon reboots.

Password Recovery Procedure for Appliance via ROMMON

Step 1. Send 'break' key when you see ##### print on console for system loading image.Then, system will break bootup process and will go to rommon prompt. You can either do this by pressing break or ctrl+break on the keyboard or sending break from terminal program (ex: Putty Special Command -> Break, Teraterm Control -> Send Break

Caution:
Password recovery requires the system be dropped into ROMMON.
- In classic IOS, config-register setting determines if system could 'return to ROMMON'. A config-register of 0x2102 would prevent return to ROMMON upon issuing 'break'.
- By default, all 9800 appliances (9800-40, 9800-80, 9800-L) have the config-register set 0x2102. However, since they run Linux based IOS-XE, this setting is ignored and only way to prevent return to ROMMON is to configure # no service password-recovery.

Caveat: On 9800-L running ROMMON older than 16.12(3r), this bit in config-register is honored preventing 'break' into ROMMON to do password-recovery.
Fix:If running older ROMMON, upgrade ROMMON using instructions documented at: https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/config-guide/b_upgrade_fpga_c9800.html#id_132237
Workaround If upgrade cannot be done; modify the config-register to 0x2002 as a workaround and prevent getting locked out of ROMMON

File size is 0x01d191f3
Located C9800-rpboot.16.10.01.SPA.pkg 
Image size 30511603 inode num 874837, bks cnt 7450 blk size 8*512
################################################################################
################################################################################
################################################################################
##########################################################
Boot image size = 30511603 (0x1d191f3) bytes

ROM:RSA Self Test Passed
ROM:Sha512 Self Test Passed

Package header rev 3 structure detected
Calculating SHA-1 hash...done
validate_package_cs: SHA-1 hash:
	calculated e36f46af:2c06b38d:eeb6e65b:ffaeb429:a6982d29
	expected   e36f46af:2c06b38d:eeb6e65b:ffaeb429:a6982d29
Validating main package signatures


monitor: command "boot" aborted due to user interrupt

rommon 1 >

Step 2.Change config register, to 0x2142 using command "confreg 0x2142" from rommon prompt.

rommon 1 > confreg 0x2142

You must reset or power cycle for new config to take effect

Step 3. To save rommon config change, execute "sync" at the rommon prompt, "reset" rommon to applied change from rommon prompt.

rommon 2 > sync
rommon 3 > reset

Resetting .......




Initializing Hardware ...

System integrity status: 90170200 12030107


System Bootstrap, Version 16.10(2r), RELEASE SOFTWARE
Copyright (c) 1994-2018  by cisco Systems, Inc.

Current image running: Boot ROM0
Last reset cause: LocalSoft

C9800-40-K9 platform with 33554432 Kbytes of main memory

File size is 0x000015c9
Located packages.conf 
Image size 5577 inode num 874834, bks cnt 2 blk size 8*512
#
File size is 0x01d191f3
Located C9800-rpboot.16.10.01.SPA.pkg 
Image size 30511603 inode num 874837, bks cnt 7450 blk size 8*512
################################################################################
################################################################################
################################################################################
##########################################################
Boot image size = 30511603 (0x1d191f3) bytes

ROM:RSA Self Test Passed
ROM:Sha512 Self Test Passed

Package header rev 3 structure detected
Calculating SHA-1 hash...done
validate_package_cs: SHA-1 hash:
	calculated e36f46af:2c06b38d:eeb6e65b:ffaeb429:a6982d29
	expected   e36f46af:2c06b38d:eeb6e65b:ffaeb429:a6982d29
Validating main package signatures

RSA Signed RELEASE Image Signature Verification Successful.
Image validated
Jun 21 02:30:21.565: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger
Jun 21 02:30:24.561: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger

Both links down, not waiting for other chassis
Chassis number is 1
Jun 21 02:30:25.327: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger
Jun 21 02:30:27.293: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger
Jun 21 02:30:33.770: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger
Jun 21 02:30:37.045: %PMAN-3-PROC_EMPTY_EXEC_FILE: R0/0: pvp: Empty executable u
sed for process bt_logger

              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 IOS Software [Gibraltar], C9800 Software (C9800_IOSXE), Version 16.10.1, R
ELEASE SOFTWARE (fc4)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2018 by Cisco Systems, Inc.
Compiled Mon 19-Nov-18 08:27 by mcpre



PLEASE READ THE FOLLOWING TERMS CAREFULLY. INSTALLING THE LICENSE OR
LICENSE KEY PROVIDED FOR ANY CISCO SOFTWARE PRODUCT, PRODUCT FEATURE,
AND/OR SUBSEQUENTLY PROVIDED SOFTWARE FEATURES (COLLECTIVELY, THE
"SOFTWARE"), AND/OR USING SUCH SOFTWARE CONSTITUTES YOUR FULL
ACCEPTANCE OF THE FOLLOWING TERMS. YOU MUST NOT PROCEED FURTHER IF YOU
ARE NOT WILLING TO BE BOUND BY ALL THE TERMS SET FORTH HEREIN.

Your use of the Software is subject to the Cisco End User License Agreement
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ensure that your systems and networks are prepared for a shutdown of the
Software feature.


cisco C9800-40-K9 (1GL) processor (revision 1GL) with 7866660K/6147K bytes of me
mory.
FIPS: Flash Key Check : Key Not Found, FIPS Mode Not Enabled

Processor board ID TTM22500DAL
1 Virtual Ethernet interface
4 Ten Gigabit Ethernet interfaces
32768K bytes of non-volatile configuration memory.
33554432K bytes of physical memory.
26255359K bytes of eUSB flash at bootflash:.
234365527K bytes of SATA hard disk at harddisk:.
0K bytes of WebUI ODM Files at webui:.

Base Ethernet MAC Address          : D4:C9:3C:CC:F2:E0

Installation mode is INSTALL



Press RETURN to get started!


*Jun 21 02:31:00.165: %IOSXE_PLATFORM-3-WDC_NOT_FOUND: WDC returned length: 0
*Jun 21 02:31:00.185: %SMART_LIC-6-EXPORT_CONTROLLED: Usage of export controlled
 features is not allowedAdding registry invocations for the WLC platform

*Jun 21 02:31:01.743: %SMART_LIC-6-AGENT_READY: Smart Agent for Licensing is ini
tialized
*Jun 21 02:31:01.743: %SMART_LIC-6-AGENT_ENABLED: Smart Agent for Licensing is e
nabled 
*Jun 21 02:31:01.743: %SMART_LIC-6-EXPORT_CONTROLLED: Usage of export controlled
 features is not allowed
*Jun 21 02:31:04.732: mcp_pm_subsys_init : Init done sucessfullyRA Tracing tool 
registry return: 0SID Manager, starting initialization ...

*Jun 21 02:31:05.511: Notifications initializedSID Manager, completed initializa
tion ...

*Jun 21 02:31:07.298: %SPANTREE-5-EXTENDED_SYSID: Extended SysId enabled for typ
e vlan
*Jun 21 02:31:08.999: %CRYPTO-4-AUDITWARN: Encryption audit check could not be p
erformed
*Jun 21 02:31:09.081: %VOICE_HA-7-STATUS: CUBE HA-supported platform detected.
*Jun 21 02:31:09.317: %IOSXE_VMAN-3-MSGINITFAIL: Failed to initialize required V
irt-manager resource: Initalize MQIPC
*Jun 21 02:31:09.333: mcp_pm_init_done : Called
*Jun 21 02:31:09.338: %LINK-3-UPDOWN: Interface Lsmpi0, changed state to up
*Jun 21 02:31:09.345: %LINK-3-UPDOWN: Interface EOBC0, changed state to up
*Jun 21 02:31:09.345: %LINEPROTO-5-UPDOWN: Line protocol on Interface VoIP-Null0
, changed state to up
*Jun 21 02:31:09.346: %LINEPROTO-5-UPDOWN: Line protocol on Interface LI-Null0, 
changed state to up
*Jun 21 02:31:09.346: %LINK-3-UPDOWN: Interface GigabitEthernet0, changed state 
to down
*Jun 21 02:31:09.351: %LINK-3-UPDOWN: Interface LIIN0, changed state to up
*Jun 21 02:30:33.738: %PMAN-3-PROC_EMPTY_EXEC_FILE: Chassis 1 R0/0: pvp: Empty e
xecutable used for process bt_logger
*Jun 21 02:30:37.011: %PMAN-3-PROC_EMPTY_EXEC_FILE: Chassis 1 R0/0: pvp: Empty e
xecutable used for process bt_logger
*Jun 21 02:30:39.576: %CMFP-6-CRYPTO_MODULE: Chassis 1 R0/0: cman_fp: Crypto Har
dware Module is present
*Jun 21 02:31:01.754: %LMRP-3-RTU_UNINITIALIZED: Chassis 1 R0/0: lman: RTU not y
et initialized: stack enabled 0
*Jun 21 02:31:09.489: %SMART_LIC-6-HA_ROLE_CHANGED: Smart Agent HA role changed 
to Active.
*Jun 21 02:31:10.295: %IOSXE_MGMTVRF-6-CREATE_SUCCESS_INFO: Management vrf Mgmt-
intf created with ID 1, ipv4 table-id 0x1, ipv6 table-id 0x1E000001
*Jun 21 02:31:10.344: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, cha
nged state to down
*Jun 21 02:31:10.345: %LINEPROTO-5-UPDOWN: Line protocol on Interface Lsmpi0, ch
anged state to up
*Jun 21 02:31:10.394: %LINEPROTO-5-UPDOWN: Line protocol on Interface EOBC0, cha
nged state to up
*Jun 21 02:31:10.394: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth
ernet0, changed state to down
*Jun 21 02:31:10.394: %LINEPROTO-5-UPDOWN: Line protocol on Interface LIIN0, cha
nged state to up
*Jun 21 02:31:10.966: %ONEP_BASE-6-SS_ENABLED: ONEP: Service set Base was enable
d by Default
*Jun 21 02:31:12.842: %SYS-6-STARTUP_CONFIG_IGNORED: System startup configuratio
n is ignored based on the configuration register setting.
*Jun 21 02:31:12.854: %IOSXE_OIR-6-REMSPA: SPA removed from subslot 0/0, interfa
ces disabled
*Jun 21 02:31:12.913: %SPA_OIR-6-OFFLINECARD: SPA (BUILT-IN-4X10G/1G) offline in
 subslot 0/0
*Jun 21 02:31:12.919: %IOSXE_OIR-6-INSCARD: Card (fp) inserted in slot F0
*Jun 21 02:31:12.920: %IOSXE_OIR-6-ONLINECARD: Card (fp) online in slot F0
*Jun 21 02:31:12.946: %IOSXE_OIR-6-INSCARD: Card (cc) inserted in slot 0
*Jun 21 02:31:12.946: %IOSXE_OIR-6-ONLINECARD: Card (cc) online in slot 0
*Jun 21 02:31:13.111: % Redundancy mode change to SSO

*Jun 21 02:31:13.112: %VOICE_HA-7-STATUS: NONE->SSO; SSO mode will not take effe
ct until after a platform reload.
*Jun 21 02:31:13.231: %IOSXE_OIR-6-INSSPA: SPA inserted in subslot 0/0
*Jun 21 02:31:14.793: %SYS-5-RESTART: System restarted --
Cisco IOS Software [Gibraltar], C9800 Software (C9800_IOSXE), Version 16.10.1, R
ELEASE SOFTWARE (fc4)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2018 by Cisco Systems, Inc.
Compiled Mon 19-Nov-18 08:27 by mcpre
*Jun 21 02:31:14.834: %CRYPTO-6-ISAKMP_ON_OFF: ISAKMP is OFF
*Jun 21 02:31:14.834: %CRYPTO-6-GDOI_ON_OFF: GDOI is OFF
*Jun 21 02:31:16.976: %LINK-3-UPDOWN: Interface GigabitEthernet0, changed state 
to up
*Jun 21 02:31:17.079: %SYS-6-BOOTTIME: Time taken to reboot after reload =  325 
seconds
*Jun 21 02:31:17.977: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEth
ernet0, changed state to up
*Jun 21 02:31:21.579: %SPA_OIR-6-ONLINECARD: SPA (BUILT-IN-4X10G/1G) online in s
ubslot 0/0
*Jun 21 02:31:21.638: %IOSXE_SPA-6-UPDOWN: Interface TenGigabitEthernet0/0/0, li
nk down due to remote fault
*Jun 21 02:31:21.708: %IOSXE_SPA-6-UPDOWN: Interface TenGigabitEthernet0/0/1, li
nk down due to local fault
*Jun 21 02:31:21.748: %IOSXE_SPA-6-UPDOWN: Interface TenGigabitEthernet0/0/2, li
nk down due to local fault
*Jun 21 02:31:21.788: %IOSXE_SPA-6-UPDOWN: Interface TenGigabitEthernet0/0/3, li
nk down due to local fault
*Jun 21 02:31:21.855: %PNP-6-PNP_DISCOVERY_STOPPED: PnP Discovery stopped (Start
up Config Present)
*Jun 21 02:31:23.541: %LINK-3-UPDOWN: Interface TenGigabitEthernet0/0/0, changed
 state to down
*Jun 21 02:31:23.571: %LINK-3-UPDOWN: Interface TenGigabitEthernet0/0/1, changed
 state to down
*Jun 21 02:31:23.572: %LINK-3-UPDOWN: Interface TenGigabitEthernet0/0/2, changed
 state to down
*Jun 21 02:31:23.575: %LINK-3-UPDOWN: Interface TenGigabitEthernet0/0/3, changed
 state to down
*Jun 21 02:31:24.680: %IOSXE_SPA-6-UPDOWN: Interface TenGigabitEthernet0/0/0, li
nk down due to local fault
*Jun 21 02:31:23.618: %LINK-3-UPDOWN: SIP0/0: Interface TenGigabitEthernet0/0/0,
 changed state to down
*Jun 21 02:31:29.036: %PKI-2-NON_AUTHORITATIVE_CLOCK: PKI functions can not be i
nitialized until an authoritative time source, like NTP, can be obtained.
*Jun 21 02:31:29.491: %LINK-3-UPDOWN: Interface TenGigabitEthernet0/0/0, changed
 state to up
*Jun 21 02:31:30.492: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabit
Ethernet0/0/0, changed state to up
*Jun 21 02:31:29.491: %LINK-3-UPDOWN: SIP0/0: Interface TenGigabitEthernet0/0/0,
 changed state to up
*Jun 21 02:31:30.495: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, cha
nged state to up
*Jun 21 02:31:37.119: %CRYPTO_ENGINE-5-KEY_ADDITION: A key named CISCO_IDEVID_SU
DI_LEGACY has been generated or imported by pki-sudi
*Jun 21 02:31:39.050: %CRYPTO_ENGINE-5-KEY_ADDITION: A key named CISCO_IDEVID_SU
DI has been generated or imported by pki-sudi

Step 4. Now system will boot without any config, Ignore startup config wizard.

Step 5. Once system comes up, copy startup-config to running-config.

Step 6. Reconfigure enable password or loging credentials, and check if you can access to the device via telnet or ssh.
  

C9800-40#telnet 172.22.175.1
Trying 172.22.175.1 ... Open


User Access Verification

Username: admin
Password:
C9800-40#

Step 7. Change config-register back to 0x2002

C9800-40(config)#config-register 0x2002

NOTICE : Please do not use 0x2102. With 0x2102, you may not be allowed sending break anymore.

1. save config.
   

   C9800-40#write memory 
   Building configuration...
   [OK]
   

Password Recovery Procedure for Appliance via USB

Boot the WLC from ROMMON

If you get stuck in rommon and boot does not work:

rommon 12 > boot
File size is 0x0001dfe6
Located memleak.tcl 
Image size 122854 inode num 12, bks cnt 30 blk size 8*512
##
Boot image size = 122854 (0x1dfe6) bytes

Unsigned package found, aborting package loading...

Failed to Free memory block at address 0x00000000cd50b000
File size is 0x00000023
Located pnp-tech-time 
Image size 35 inode num 13, bks cnt 1 blk size 8*512

Boot image size = 35 (0x23) bytes

Unsigned package found, aborting package loading...

Failed to Free memory block at address 0x00000000cd4d3000
File size is 0x0001ad3f
Located pnp-tech-discovery-summary 
Image size 109887 inode num 14, bks cnt 27 blk size 8*512
#
Boot image size = 109887 (0x1ad3f) bytes

Unsigned package found, aborting package loading...

Failed to Free memory block at address 0x00000000cd49b000
File size is 0x00000268
Located vlan.dat 
Image size 616 inode num 15, bks cnt 1 blk size 8*512

Boot image size = 616 (0x268) bytes

Unsigned package found, aborting package loading...

Failed to Free memory block at address 0x00000000cd463000
boot: cannot determine first file name on device "bootflash:/"
rommon 13 > 

And the flash does not have any image to boot from:

rommon 13 > dir bootflash:
File System: EXT2/EXT3

11         16384     drwx------     lost+found
850305     4096      drwxr-xr-x     .installer
588673     4096      drwxrwxrwx     .prst_sync
948417     4096      drwxr-xr-x     .rollback_timer
1381745    4096      drwxr-xr-x     dc_profile_dir
12         122854    -rw-r--r--     memleak.tcl
506913     4096      drwxr-x---     vman_fdb
670433     4096      drwxr-xr-x     .dbpersist
793073     4096      drwxr-xr-x     onep
13         35        -rw-r--r--     pnp-tech-time
14         109887    -rw-r--r--     pnp-tech-discovery-summary
15         616       -rw-r--r--     vlan.dat

You can recover the box by either:

• Loading an image through a USB pen drive
• Loading an image through Gigabit0 (out of band management interface)

Load image through USB

Step 1. Have a USB pen drive with the .bin file to be loaded to the 9800 controller (on 9800-80, due to CSCvn82287 , a USB 3.0 flash drive may not be recognized in ROMMON). Note that the procedure is the same in case of a virtual 9800-CL but you will have to plug the USB drive on the VMhost and map it to the VM.

Step 2. Connect the USB driver to the USB port 0 of the 9800

Front view:

Step 3. Login by console to the controller and ensure it can read the USB

rommon 19 > dir usb0:
File System: FAT32
!
!--Output omitted--
!
335644   1009389904-rw-     <filename>SSA.bin

Step 4. Configure the 9800 to boot from the USB image

rommon 21 > boot usb0:<filename>.bin
Located qwlc-universalk9_wlc.BLD_V169_THROTTLE_LATEST_20180601_191011.SSA.bin, start cluster is 335644 

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

Step 5. Once the 9800 is up, copy the image from the USB to the booflash:

WLC# copy usb0:<filename>.bin bootflash:
Destination filename [qwlc-universalk9_wlc.BLD_V169_THROTTLE_LATEST_20180601_191011.SSA.bin]?
Copy in progress...CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC

Step 6. It is best to change the 9800 from bundle mode to install mode

When you boot the controller from a USB, it boots in Bundle mode:

!
!--Output omitted--
!
FIPS: Flash Key Check : Key Not Found, FIPS Mode Not Enabled

Processor board ID TTM22071510
1 Virtual Ethernet interface
4 Ten Gigabit Ethernet interfaces
32768K bytes of non-volatile configuration memory.
33554432K bytes of physical memory.
26910719K bytes of eUSB flash at bootflash:.
234365527K bytes of SATA hard disk at harddisk:.
15243680K bytes of USB flash at usb0:.
0K bytes of WebUI ODM Files at webui:.

Base Ethernet MAC Address          : 00:A3:8E:23:A2:40

Installation mode is BUNDLE 

%INIT: waited 0 seconds for NVRAM to be available

In the web UI, starting from 16.12, you can chose to move to INSTALL mode at the next upgrade (provide any software file, including current release to move to INSTALL mode)

Step 7. Edit the boot variable if it is not pointing towards a "packages.conf" file already

WLC# conf t
Enter configuration commands, one per line.  End with CNTL/Z.
WLC(config)# no boot system      
WLC(config)# boot system bootflash:packages.conf
WLC(config)# end 
WLC# write
Building configuration...
[OK]
WLC# show boot
BOOT variable = flash:packages.conf,12;
CONFIG_FILE variable does not exist
BOOTLDR variable does not exist
Configuration register is 0x2102

Standby not ready to show bootvar

Make sure that the config register is 0x2002

 Step 8. Reload the WLC

WLC# reload

After this, the controller boots up in Install mode

WLC# show version
!
!--Output omitted--
!
Installation mode is INSTALL Configuration register is 0x2002

Load an image from TFTP

To load an image from the network, you must have the GigabitEthernet0 management port physically connected to an access port.

From the rommon, you can verify the variables at any time by typing "set"

rommon 1 > set
PS1=rommon ! >
?=0
DEFAULT_GATEWAY=10.1.1.1
ETHER_SPEED_MODE=4
TFTP_RETRY_COUNT=36
SWITCH_NUMBER=1
DLC_DONE=TRUE
RET_2_RTS=
RET_2_RCALTS=
MCP_STARTUP_TRACEFLAGS=00000000:00000000
TFTP_MACADDR=00:db:ad:ba:d0:52
IP_SUBNET_MASK=255.255.255.0
IP_ADDRESS=10.1.1.152
TFTP_SERVER=10.1.1.1
TFTP_FILE=C9800-80-universalk9_wlc.BLD_V1610_1_THROTTLE_LATEST_20181016_174328_2.bin
BSI=0
RANDOM_NUM=1650632109

You can then set the variables one by one. There is  no need to type "set" before the variable name like in some other devices ROMMON. Make sure to not make any typo when typing the variable name as there is no verification of any sort.

rommon 2 > IP_ADDRESS=10.48.71.113
rommon 3 > IP_SUBNET_MASK=255.255.255.128
rommon 4 > DEFAULT_GATEWAY=10.48.71.5

Once the IP settings are in place, you can boot from a TFTP image  with the following command:

rommon 5 > boot tftp://10.48.39.33/C9800-80-universalk9_wlc.16.10.01.SPA.bin

          IP_ADDRESS: 10.48.71.113
      IP_SUBNET_MASK: 255.255.255.128
     DEFAULT_GATEWAY: 10.48.71.5
         TFTP_SERVER: 10.48.39.33
           TFTP_FILE: C9800-80-universalk9_wlc.16.10.01.SPA.bin
        TFTP_MACADDR: 70:6d:15:35:99:ff
        TFTP_VERBOSE: Progress
    TFTP_RETRY_COUNT: 36
        TFTP_TIMEOUT: 7200
        TFTP_BLKSIZE: 1460
       TFTP_CHECKSUM: Yes
          ETHER_PORT: 3
    ETHER_SPEED_MODE: 1000MB/HD
link up
Receiving C9800-80-universalk9_wlc.16.10.01.SPA.bin from 10.48.39.33 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

 You will then end up in the IOS command line. Don't forget to actually copy the IOS image to the flash or harddisk and set the boot variable correctly. You can resume the procedure from the USB section above as of step 6 once the file is copied in the flash or harddisk:

 Other useful ROMMON commands

The command dev lists the storage devices available (bootflash,harddisk,usb...)

The command showmon shows the ROMMON version