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Difference between a 2500 and 2600 in terms of booting of IOS sequence

What is the difference in the booting of IOS sequence for a 2500 and a 2600 router? Does the 2500 boot 1) ROM 2) Falsh and 3) Network TFTP and the 2600 boots 1) Flash 2) Netwrok TFT 3) ROM

Also where the IOS run from in the 2500 and in the 2600?


Re: Difference between a 2500 and 2600 in terms of booting of IO

Booting sequence for all routers are preety much the same. The

only booting differences between a c2500 and c2600

is that c25000 boots its IOS from flash directly

while a c2600 first decompresses the ziped IOS in flash to

DRAM and the run the IOS from DRAM which leaves the flash free

to access, delete or upload a new image on.

The booting sequece for all router is

1. power on or reload

2. do a Power on self test (diagnostic from bootrom)

3. check the configuration register

0X2100 = boot to rommon

0X2101 = boot from bootflash to rommon

0x2102 = boot using the netboot statement in the config.

If no netboot statement is present in the config and the register is set to 0x2102, then

1 boot the first image in flash

2 if it fails boot the second image

3a. if it fails in 2500 boot the bootflash image

3b. If it fails in a 2600 bootfrom rommon and go to rommon.

4. attention is needed if 3 is executed.

The reason c2600 have no bootflash is becasue the platform can be recovered from rommon while

2500 has bootflash which is a subset of IOS which else recover from platforms

that has bootflash and cannot boot IOS for some reason.

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