Hi,
There is no limit for configuring objects in a single context ASA.
However, there is a limitation on the number of access-control elements on a specific hardware.
There is no hard-coded limit on the number of elements (access control entries) in an ACL, which is bound only by memory. Each ACE uses a minimum of 212 bytes of RAM. However maximum performance may decrease (typically by 10 to 15 percent as you reach or exceed the recommended maximum number of ACEs.
Please check the link for ASA 5585 ( Section: What is the maximum ACL limit on ASA)?
https://www.cisco.com/c/en/us/products/collateral/security/adaptive-security-appliance-asa-software/qa_c67-731962.html
Also, is it possible to block IP address ranges by geographical region versus ip host or cidr block addresses?
On ASA you can only use CIDR block to block IP address, only if use Sourcefire module on ASA you would be able to block on geographical region.
Regards,
Aditya
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