Because the Cisco 3600 series routers have two Flash SIMM slots and there is no requirement that the Flash SIMMs be the same size, it is possible to add a second Flash SIMM on a router with only one SIMM installed and copy an image to it using TFTP. In order to accomplish this, partitioning is required. This is less time-consuming than an xmodem procedure.
If the 3600 series router has a Cisco IOS image installed on one Flash SIMM and you wish to replace it with a larger Flash SIMM, perform the steps below. This example demonstrates going from one 8 MB Flash SIMM to two 16 MB Flash SIMMs.
Power off the router.
Install one of the 16 MB Flash SIMMs in the second slot.
Power the router back on. When the router loads, there should be 24 MB of Flash showing up in the show version command output.
Issue the partition flash[number-of-partitions] [partition-size] global configuration command. This is an example of the command output:
router(config)#partition flash 2 8 16 router(config)#^Z (ctrl z to exit) router#
The two Flash SIMMs are now partitioned.
Copy the Cisco IOS file to the second partition. If you are copying the file from the original 8 MB SIMM, issue the copyflash:1: <filename> flash:2: command.
This is an example of the command output for the filename c3640-i-mz.122-10.bin: