The requested memory allocation is not available from the specified memory pool. The router memory has been exhausted or fragmented.

The smart_init is a sw module supposed to estimate the i/o size needed for a hw/sw config. It cuts a portion of the total memory
size and allocates it for the i/o pool, the rest remaining for the processor pool. The traffic pattern this router experiences might be a little bit too
bursty. To avoid that, we might want to disable the smart_init and allocate manually an amount of memory for the i/o pool.

Action plan: please enter at the global config prompt:

2811(config)# memory-size iomem 15

This will disable the smart_init module and will allocate 15% of the total dram to the i/o pool. This will clearly avoid the i/o pool size shortage and
get to the fragmentation we totally dislike.

Once configured, please reload the router to take effect the configuration.
Once done, you'll see this router run fine.