Software recovery for Supervisor III or Supervisor IV on the Catalyst 4000

[TCC_2]

Core issue

The Catalyst 4000 has an onboard bootflash Flash system that is used to store image files. During normal bootup, the supervisor typically loads a software image from Flash. When an image is already loaded in RAM, the Flash is not needed for switch operation.

While the switch is up and operational, upgrade the software by issuing the traditional copy tftp flash command.

However, if you encounter a problem with the software you currently have in Flash and are unable to fully boot up the switch (or if the switch ends up in ROM Monitor [ROMmon] mode and you need to get the switch back up), perform a netboot procedure.

Resolution

A netboot allows you to download an image from a TFTP server directly into RAM, where the supervisor can run it. This procedure does not create any files on the Flash system. It only allows you to bring up your switch and perform a normal software download.

Note: When your switch is in ROM, you must be directly connected to the console. The only network port that will be active is interface ME1.

For the recovery procedure, perform these steps:

1. Verify that all the variables are set and that you are able to reach the TFTP server, as shown in this example:
   show interface
   me1: inet 172.20.58.227 netmask 255.255.255.0 broadcast 172.20.58.255
   
2. If you do not see an IP address on the ME1 interface, set the IP address by issuing the set interface me1 [netmask] command.

   This is an example:

   
   

   set interface me1 172.20.58.227 255.255.255.0

   rommon 2 >
   show ip route
   Destination Gateway Interface
   ----------------------- --------------------
   default 0.0.0.0 me1
   

   In this example, there is no default gateway set.

3. If the TFTP server is not on the same network, set a default route.
4. Set the default gateway, if needed.

   This is an example:

   
   rommon 3 >
   set ip route default 172.20.58.1
   
5. If the command gives you no response, issue the show ip route command for verification.

   This is an example:

   
   rommon 4 >
   show ip route
   Destination Gateway Interface
   ----------------------- --------
   default 172.20.58.1 me1<
   
6. Verify that the TFTP server variable is set correctly.

   Issuing the set command by itself displays the environment variables, as shown in this example:

   
   rommon 5 >
   set
   PS1=rommon ! >
   AutobootStatus=success
   MemorySize=32
   DiagBootMode=post
   ?=0
   ROMVERSION=4.4(1)
   WHICHBOOT=bootflash:cat4000.4-4-1.bin
   BOOT=bootflash:cat4000.4-4-1.bin,1;
   
7. Since you do not have the TFTP server variable as part of the environment, set the variable before proceeding.
8. Verify that the variable is actually in the environment.
9. Ping the server to validate connectivity.
10. You do not need to have the TFTP server environment variable set to ping the server.

    It is required to access the file on the server by issuing the boot command, as shown in this example.

    
    rommon 6 >
    Tftpserver=172.20.59.67
    !--- Setting TFTP server variable.
    
    rommon 7 > set
    !--- Verifying the setting.
    PS1=rommon
    ! >
    AutobootStatus=success
    MemorySize=32
    DiagBootMode=post
    Tftpserver=172.20.59.67
    ?=0
    ROMVERSION=4.4(1)
    WHICHBOOT=bootflash:cat4000.4-4-1.bin
    BOOT=bootflash:cat4000.4-4-1.bin,1;
11. Netboot the system.

    rommon 9 > boot cat4000.4-4-1.bin

    After netbooting the system, you will get the switch console.

12. When the system is fully operational again, copy the valid image to the Flash by issuing the copy tftp flash command. This makes sure that the switch boots with the valid image in the next reload.