2
Category
ACL number
IP version
Match criteria
IPv4
Source IPv4 address, destination IPv4 address,
protocols over IPv4, and other Layer 3 and Layer
4 header fields
Advanced ACLs 3000 to 3999
IPv6
Source IPv6 address, destination IPv6 address,
protocols over IPv6, and other Layer 3 and Layer
4 header fields
Ethernet frame
header ACLs
4000 to 4999
IPv4 and IPv6
Layer 2 header fields, such as source and
destination MAC addresses, 802.1p priority,
and link layer protocol type
ACL numbering and naming
Each ACL category has a unique range of ACL numbers. When creating an ACL, you must assign it a
number for identification. In addition, you can assign the ACL a name for the ease of identification. After
creating an ACL with a name, you cannot rename it or delete its name.
For an Ethernet frame header, the ACL number and name must be globally unique. For an IPv4 basic or
advanced ACL, its ACL number and name must be unique among all IPv4 ACLs, and for an IPv6 basic
or advanced ACL, among all IPv6 ACLs. You can assign an IPv4 ACL the same number and name as an
IPv6 ACL.
Match order
The rules in an ACL are sorted in a specific order. When a packet matches a rule, the device stops the
match process and performs the action defined in the rule. If an ACL contains overlapping or conflicting
rules, the matching result and action to take depend on the rule order.
The following ACL match orders are available:
•
config—Sorts ACL rules in ascending order of rule ID. A rule with a lower ID is matched before a
rule with a higher ID. If you use this approach, carefully check the rule content and order.
•
auto—Sorts ACL rules in depth-first order. Depth-first ordering ensures that any subset of a rule is
always matched before the rule.
lists the sequence of tie breakers that depth-first ordering
uses to sort rules for each type of ACL.
Table 1
Sort ACL rules in depth-first order
ACL category
Sequence of tie breakers
IPv4 basic ACL
1.
More 0s in the source IP address wildcard (more 0s means a narrower IP
address range)
2.
Smaller rule ID