As one of the most popular Cisco switches, Cisco 2960 (taking WS-C2960S-48TS-L for example) are widely applied worldwide. However, it’s hard to avoid all the problems with any good device. We are always asked such kind of questions or complaints, “I am looking for ways to avoid deleting files from the flash in a Switch 2960, I found some scripts TCL / EEM but this switch does not support EEM (IOS c2960-lanbasek9-mz.122-58.SE2.bin). Who can help to solve this problem?”
How to solve this problem?
Generally speaking, guys with that problem could assign all unauthorized users a privilege less than 15 where the delete command is not allowed. However, this would be more of an administrative burden; additionally, they also could use AAA command authorization with a TACACS+ server to deny access to the “delete” command except for those users privileged enough to do this. Though that idea AAA is good, but it would require a previous configuration loaded on the Switch, and if the student clears the startup-config and restart the machine and lost the configuration to verify the AAA, it’s invalid at all.
Thus, we’d better know the basic cause of Cisco Catalyst 2960 fixed configuration boot errors. As far as I know, when Catalyst fixed configuration switches experience boot errors, these conditions can apply:
The switch is in a continuous reboot.
The switch displays the switch: prompt.
The error loading flash: message appears.
You know, we cannot describe or summarize all the problems at a word, we only share the solution for booting errors resulting from flash deleted:
First, we need to have the IOS file, if no backup the original file, you can find the same version of IOS to replace.
Methods: X-Modem
According to my experience, when Flash is deleted, restart cannot enter the system, the only way to recover by X-Modem as far as I know.
Steps of recovering:
First open the super terminal, enter rommon mode (Ctrl+Break key combination), type confreg, as follows:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Rommon 1 > confreg enter
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 (yes)
Enable “diagnostic mode” [n]? Y/n: n (no)
Enable “use net in IP BCAST address” [n]? Y/n: n (no)
Disable “load ROM after netboot fails” [n]? Y/n: n (no)
Enable “use all zero broadcasts” [n]? Y/n: n (no)
Enable “break/abort has effect” [n]? Y/n: n (no)
Enable “ignore system config info” [n]? Y/n: n (no)
Change console baud rate? Y/n [n]: Y (yes)
Enter rate: 0 = 9600, 1 = 4800, 2 = 1200, 3 = 2400
4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200: 7 ([0] 7, XMODEM 115200 of the maximum transmission rate)
Change the boot characteristics? Y/n [n]: n (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 (no)
You must reset or power cycle for new config to take effect
Rommon 2 > Reset enter
Note: before the type reset key, start by defining a speed (Computer – port attribute my —- serial speed is 115200), then remember to modify the super terminal set at a rate of 115200, otherwise it’ll be garbled! Then close the super terminal, the re-establishment of a super terminal connection, (during the system restart) after the start, there
Rommon 1> prompt
Then, input
Rommon 1> XMODEM -r
Do not start the sending program yet…
Invoke this application only for disaster recovery.
Do you wish to continue? Y/n [n]: Y (yes)
Ready to receive file…
At this time, in the super terminal on the menu “transfer” – “to send the file, select” IOS image file location and choose to use the “XMODEM” agreement, click the “send” button
Then wait for about 10-20 minutes to 3-6M IOS fill (modified back to the computer serial port and super terminal, router confreg under the XMODEM 9600 transmission rate)
(videre note: the actual use of the time, I found this command is not successful, later found on the line con 0 with a speed 115200, so even if the modified register success, start router and implementation of speed 115200. If you have this problem, remember to turn off the no statement)
Router>en enters the new IOS privileged mode
The resumption of the Router#reload system
Proceed with reload? [confirm] enter
00:01:04:%SYS-5-RELOAD: Reload requested
System Bootstrap, Version 11.3 (2) XA4, RELEASE SOFTWARE (FC1)
Copyright (c) 1999 by Cisco Systems, Inc.
TAC: Home:SW:IOS:Specials for info
PC = 0xfff0a530, Vector = 0×500, SP = 0x680127b0
C2600 platform with 24576 Kbytes of main memory
PC = 0xfff0a530, Vector = 0×500, SP = 0×80004684
Monitor: command “boot” aborted due to user interrupt
Rommon 1 > confreg (enter “confreg” command)
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]: Y (yes)
Enable “diagnostic mode” [n]? Y/n: n (no)
Enable “use net in IP BCAST address” [n]? Y/n: n (no)
Disable “load ROM after netboot fails” [n]? Y/n: n (no)
Enable “use all zero broadcast” [n]? Y/n: n (no)
Enable “break/abort has effect” [n]? Y/n: n (no)
Enable “ignore system config info” [n]? Y/n: n (no)
Change console baud rate? Y/n [n]: Y (yes)
Enter rate: 0 = 9600, 1 = 4800, 2 = 1200, 3 = 2400
4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200 ([7]: 0 XMODEM transmission 0, switch back to using the standard rate of 9600)
Change the boot characteristics? Y/n [n]: n (no)
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]: n?
You must reset or power cycle for new config to take effect
Rommon 2.
This manual change back to the computer serial port and super terminal 2 transmission rate is 9600
And then typing
Rommon 2 >reset WS-C2960S-48TS-L
(You’d better power off)
More tips on Cisco 2960 and Cisco boot at:
How Cisco routers boot Cisco IOS software?
How to Configure Cisco 2960 S to Route?
12 Most Popular Cisco 2960-S Specs Including 2960S-24PS-L and 2960S-24TS-S
