¿Es necesaria CompactFlash en el arranque?

joseagarcialopez · ‎07-01-2013

Buenas tardes.

Me pongo en contacto con vosotros para ver si podéis ayudarme en una duda que tengo y me está volviendo loco.

Tengo un router 2811 con flash externa (Compact Flash, CF) el cual he modificado para que como primera opción obtenga la IOS de un servidor FTP externo (mediante comando 'boot system ftp...'), y con un valor de confreg de 0x2102.

El caso es que si hago un reload del equipo sin la CF metida no consigo que arranque a pesar de que tener un comando 'boot system' en la NVRAM hace que lo ejecute primero y haga 'override' de la flash (CF en este caso), quedándose en modo rommon. Si introduzco la CF, el router arraca sin problemas y accede al servidor FTP a coger la IOS.

Mi duda es si este comportamiento es debido a que extrae al comienzo el 'boot loader' de la propia CF. Si no, no entiendo para qué se usa la CF, y me gustaría saber como se puede hacer para evitarla por completo en el arranque y ponerla como segunda opción.

Agradezco cualquier comentario al respecto ya que no consigo sacarle explicación a pesar de que he leído y estudiado al respecto.

Un saludo y muchas gracias a todos

Leo Laohoo · ‎07-01-2013

If you can post this in English, I might be able to reply to your post.

joseagarcialopez · ‎07-01-2013

Hello.

I post here because I need help with a question.

I have a 2811 router with external flash (Compact Flash, CF) that I have tuned to get first of all IOS from a external FTP server (with the command 'boot system ftp...'), and confreg equal 0x2102.

If I do a reload with the CF out, the router doesn´t start properly and shows me the rommon mode despite of I have in the configuration 'boot system' command in NVRAM that override the start from the flash (CF in this case ). If I introduce the CF, the router begins properly and accesses to the FTP server to take the IOS.

My question is why is neccesary that CF is into the router in the boot proccess?. Maybe needs to extract the boot loader from the CF??? I´d like to know why, and I´d like to know too how I can do to bypass it as first option.

I appreciate any comments about it

Regards and thanks a lot!!!

bzendeja · ‎07-02-2013

Hola José,

Como bien notaste en tus pruebas, para iniciar el 2811 con booteo por TFTP se requiere forzosamente del boothelper en la CF para que cargue la configuración del equipo y pueda alcanzar al servidor de TFTP. Esto no se puede hacer automáticamente desde Rommon. Existe una utilería para descargar imágenes desde rommon usando el comando tftpdnld pero no se puede automatizar para hacer lo que tu requieres.

Déjame saber si esta información te sirve.

Saludos,

Bernardo

joseagarcialopez · ‎07-02-2013

Muchas gracias Bernardo.

Conozco la herramienta 'tftpdnld' y ya la había utilizado, pero no se adapta a lo que necesito.

De todas formas, has contestado a la duda que tenía, que era saber si la CF era necesaria en el arranque y ya veo que si, que no hay forma de hacerle un 'bypass'

Muy agradecido.

Un saludo

Jose

Leo Laohoo · ‎07-04-2013

If I do a reload with the CF out, the router doesn´t start properly and shows me the rommon mode despite of I have in the configuration 'boot system' command in NVRAM that override the start from the flash (CF in this case ). If I introduce the CF, the router begins properly and accesses to the FTP server to take the IOS.

Can you post the output to the command "sh version"? I want to see the configuration-register value at the bottom.

Next, I would like to ask if you can console into the router and reboot the router. I want to see the entire bootup process and the point where the router fails to load the IOS and goes into ROMmon. I would also like to see you enter the command to enable the router to boot the correct IOS.

joseagarcialopez · ‎07-05-2013

Hi Leo.

The 'show version' output is:

     Cisco IOS Software, 2800 Software (C2800NM-IPBASE-M), Version 12.4(3e), RELEASE SOFTWARE (fc2)
     Technical Support: http://www.cisco.com/techsupport
     Copyright (c) 1986-2006 by Cisco Systems, Inc.
     Compiled Tue 13-Jun-06 23:24 by alnguyen

ROM: System Bootstrap, Version 12.4(1r) [hqluong 1r], RELEASE SOFTWARE (fc1)

     Router uptime is 1 minute
     System returned to ROM by power-on
     System image file is "flash:c2800nm-ipbase-mz.124-3e.bin"

     Cisco 2811 (revision 53.50) with 251904K/10240K bytes of memory.
     2 FastEthernet interfaces
     DRAM configuration is 64 bits wide with parity enabled.
     239K bytes of non-volatile configuration memory.
     62720K bytes of ATA CompactFlash (Read/Write)

Configuration register is 0x2102

In my configuration, I have this to 'avoid' to start from CF:

boot system tftp c2800nm-ipbase-mz.124-3e.bin

If I reload now (without CF):

     Initializing memory for ECC
     .
     c2811 processor with 262144 Kbytes of main memory
     Main memory is configured to 64 bit mode with ECC enabled

     Readonly ROMMON initialized
     Compact Flash:not present
     c2811 processor with 262144 Kbytes of main memory
     Main memory is configured to 64 bit mode with ECC enabled

Readonly ROMMON initialized
rommon 1 >

If I insert the CF and reload:

     Initializing memory for ECC
     .
     c2811 processor with 262144 Kbytes of main memory
     Main memory is configured to 64 bit mode with ECC enabled

Readonly ROMMON initialized

program load complete, entry point: 0x8000f000, size: 0xe360bc
Self decompressing the image : ###################################################################################################################################################### [OK]

WHAT IS THIS IMAGE? WHY IS NOT BEING LOADED FROM TFTP SERVER IN THIS POINT?

     Smart Init is enabled
     smart init is sizing iomem
       ID            MEMORY_REQ                 TYPE
     0003E7          0X003DA000 C2811 Mainboard
                0X000021B8 Onboard USB
                0X002C29F0 public buffer pools
                0X00211000 public particle pools
     TOTAL:          0X008AFBA8

     If any of the above Memory Requirements are
     "UNKNOWN", you may be using an unsupported
     configuration or there is a software problem and
     system operation may be compromised.
     Rounded IOMEM up to: 10Mb.
     Using 3 percent iomem. [10Mb/256Mb]
     Port Statistics for unclassified packets is not turned on.

HERE IS ACCESING TO TFTP SERVER

Loading c2800nm-ipbase-mz.124-3e.bin from 1.1.1.2 (via FastEthernet0/0): !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Thanks for your help Leo

Regards

Leo Laohoo · ‎07-05-2013

OMG! You want to boot your router via TFTP???? But why???

I've had mixed results with booting from TFTP (mostly failures) and I've resorted to booting the IOS from either a CF or via USB.

joseagarcialopez · ‎07-05-2013

Hi Leo.

I´m doing some test in a lab environment because I had a problem in a operative router. I had to reload it and the CF was corrupted so the service was broke down a lot of time, and I thought that if I would had configured the boot from TFTP as secondary way, maybe I could have avoid the interruption in the network.

But tests have demostrated that boot from TFTP in a 2811 router is not the best way because if the CF is not working properly, I can´t load the IOS from an external server (TFTP or FTP).

I´ll test the boot from usbflash as an alternative way as you say.

Very grateful!!!

Leo Laohoo · ‎07-05-2013

I´ll test the boot from usbflash as an alternative way as you say.

Wait!

ISR G1's, by default, DO NOT support USB boot.

You need to upgrade the bootstrap to 12.2(13r)T11 before you can do that.

I had to reload it and the CF was corrupted so the service was broke down a lot of time,

Wait a second ... What you are trying to do, TFTP boot, and your CF being corrupted ... DOESN'T MAKE ANY SENSE. If you believe the CF is corrupted, get another one. You can get a 3rd party CF as long as the router can detect it as a valid item.

Go to your favorite electronics shop and get a CF (any brand) for testing. Follow these simple rules:

1. Size up to 2 Gb or 4 Gb;

2. Insert the CF into the slot and format the CF using the command "format flash:"

3. If the CF is supported, then you will get a favorable response. If not, go back to the electronics shop and get another brand;

4. Once the CF is formatted, copy the IOS from the TFTP to the CF. Alternatively, you can use a media card reader to copy the IOS and other file(s) to the CF.

joseagarcialopez · ‎07-07-2013

Thanks Leo