Automated protection service and clustered systems
When the automated protection service is enabled in a clustered system:
n
Each peer maintains its own count of connection failures and the trigger threshold must be reached on each
peer for the intruder's address to be blocked by that peer.
n
Addresses are blocked against only the peer on which the access failures occurred. This means that if an
address is blocked against one peer it may still be able to attempt to access another peer (from which it
may too become blocked).
n
A blocked address can only be unblocked for the current peer. If an address is blocked by another peer, you
must log in to that peer and then unblock it.
n
Category settings and the exemption list are applied across the cluster.
n
The statistics displayed on the
Automated detection overview
page are for the current peer only.
Additional information
n
When a host address is blocked and tries to access the system, the request is dropped (the host receives
no response).
n
A host address can be blocked simultaneously for multiple categories, but may not necessarily be blocked
by all categories. Those blocks may also expire at different times.
n
When an address is unblocked (either manually or after its block duration expires), it has to fail again for the
full number of times as specified by the category's trigger level before it will be blocked for a second time by
that category.
n
IPv6 host addresses are not supported (the automated protection service currently detects IPv4 host
address failures only).
n
A category is reset whenever it is enabled. All categories are reset if the system is restarted or if the
automated protection service is enabled at the system level. When a category is reset:
l
Any currently blocked addresses are unblocked.
l
Its running totals of failures and blocks are reset to zero.
n
You can view all Event Log entries associated with the automated protection service by clicking
View all
intrusion protection events
on the
Automated detection overview
page.
Cisco VCS Administrator Guide (X8.1.1)
Page 39 of 507
Network and system settings
Intrusion protection