Cisco Gigabit Ethernet Switch Module for HP p-Class BladeSystem Software Configuration Guide
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Cisco Gigabit Ethernet Switch Module for HP p-Class BladeSystem Software Configuration Guide
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Chapter 26 Configuring Network Security with ACLs
Understanding ACLs
2 input would allow Blade Server A to access the Human Resources network, but prevent Blade Server
B from accessing the same network. Port ACLs can only be applied to Layer 2 interfaces in the inbound
direction.
Figure 26-1 Using ACLs to Control Traffic to a Network
When you apply a port ACL to a trunk port, the ACL filters traffic on all VLANs present on the trunk
port. When you apply a port ACL to a port with voice VLAN, the ACL filters traffic on both data and
voice VLANs.
With port ACLs, you can filter IP traffic by using IP access lists and non-IP traffic by using MAC
addresses. You can filter both IP and non-IP traffic on the same Layer 2 interface by applying both an
IP access list and a MAC access list to the interface.
Note You cannot apply more than one IP access list and one MAC access list to a Layer 2 interface. If an IP
access list or MAC access list is already configured on a Layer 2 interface and you apply a new IP access
list or MAC access list to the interface, the new ACL replaces the previously configured one.
VLAN Maps
You use VLAN ACLs or VLAN maps to filter traffic between devices in the same VLAN. When a
VLAN map is applied to a VLAN, all packets being forwarded in the VLAN are checked against the
VLAN map.
Use VLAN maps for security packet filtering. VLAN maps are not defined by direction (input or output).
You can configure VLAN maps to match Layer 3 addresses for IPv4 traffic.
All non-IP protocols are access-controlled through MAC addresses and Ethertype using MAC VLAN
maps. (IP traffic is not access controlled by MAC VLAN maps.) You can enforce VLAN maps only on
packets going through the switch; you cannot enforce VLAN maps on traffic between hosts on a hub or
on another switch connected to this switch.
Blade Server
A
Blade Server
B
119651
Research &
Development
network
= ACL denying traffic from
Blade Server
B
and permitting traffic from
Blade Server
A
= Packet
Human
Resources
network