This document describes how to troubleshoot the Memory pool size is not valid Allowed range from 2 to 512 error message on the Cisco Adaptive Security Appliance (ASA).
When you enter the url-block url-mempool 10240 command on the ASA in Multiple mode, you receive this error message:
ciscoasa(config)# url-block url-mempool 10240 Memory pool size is not valid Allowed range from 2 to 512
The maximum URL buffer memory pool (url-mempool) size is set to 10,240 KB in Single mode on the ASA. However, in Multiple mode, each context can only have a maximum of 512 KB allocated to the url-mempool. This maximum value is hardcoded and cannot be changed.
Note: The maximum allowed URL size (configured with the url-block url-size command) must be less than the url-mempool size. As a result, before you increase the value of the url-size, you must increase the value of the url-mempool, dependent upon the mode in which the ASA runs.