Dell S4820T, Configuration Manual

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• VRF based IMPLICIT DENY Rules
NOTE: In order for the VRF ACLs to take effect, ACLs configured in the Layer 3 CAM region must
have an implicit-permit option.
You can use the
ip access-group
command to configure VRF-aware ACLs on interfaces. Using the
ip
access-group
command, in addition to a range of VLANs, you can also specify a range of VRFs as input
for configuring ACLs on interfaces. The VRF range is from 1 to 63. These ACLs use the existing V4 ACL
CAM region to populate the entries in the hardware and do not require you to carve out a separate CAM
region.
NOTE: You can configure VRF-aware ACLs on interfaces either using a range of VLANs or a range of
VRFs but not both.
IP Access Control Lists (ACLs)
In Dell Networking switch/routers, you can create two different types of IP ACLs: standard or extended.
A standard ACL filters packets based on the source IP packet. An extended ACL filters traffic based on the
following criteria:
• IP protocol number
• Source IP address
• Destination IP address
• Source TCP port number
• Destination TCP port number
• Source UDP port number
• Destination UDP port number
For more information about ACL options, refer to the Dell Networking OS Command Reference Guide .
For extended ACL, TCP, and UDP filters, you can match criteria on specific or ranges of TCP or UDP
ports. For extended ACL TCP filters, you can also match criteria on established TCP sessions.
When creating an access list, the sequence of the filters is important. You have a choice of assigning
sequence numbers to the filters as you enter them, or the Dell Networking Operating System (OS) assigns
numbers in the order the filters are created. The sequence numbers are listed in the display output of the
show config
and
show ip accounting access-list
commands.
Ingress and egress Hot Lock ACLs allow you to append or delete new rules into an existing ACL (already
written into CAM) without disrupting traffic flow. Existing entries in the CAM are shuffled to
accommodate the new entries. Hot lock ACLs are enabled by default and support both standard and
extended ACLs and on all platforms.
NOTE: Hot lock ACLs are supported for Ingress ACLs only.
Access Control Lists (ACLs)
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