
Operation Manual – ACL
H3C S3610&S5510 Series Ethernet Switches
Chapter 1 ACL Overview
1-3
1.2.2 IPv4 ACL Naming
When creating an IPv4 ACL, you can specify a unique name for it. Afterwards, you can
identify the ACL by its name.
An IPv4 ACL can have only one name. Whether to specify a name for an ACL is up to
you. After creating an ACL, you cannot specify a name for it, nor can you change or
remove the name of the ACL.
Note:
The name of an IPv4 ACL must be unique among IPv4 ACLs. However, an IPv4 ACL
and an IPv6 ACL can share the same name.
1.2.3 IPv4 ACL Match Order
Each ACL is a sequential collection of rules defined with different matching criteria. The
order in which a packet is matched against the rules may affect how the packet is
handled.
At present, the following two match orders are available:
z
config
: where packets are compared against ACL rules in the order in which they
are configured.
z
auto
: where depth-first match is performed. The term depth-first match has
different meanings for different types of ACLs.
I. Depth-first match for a basic IPv4 ACL
The following shows how your device performs depth-first match in a basic IPv4 ACL:
1) Sort rules by source IP address wildcard first and compare packets against the
rule configured with more zeros in the source IP address wildcard prior to other
rules.
2)
If two rules are present with the same number of zeros in their source IP address
wildcards, compare packets against the rule configured first prior to the other.
II. Depth-first match for an advanced IPv4 ACL
The following shows how your device performs depth-first match in an advanced IPv4
ACL:
1)
Sort rules by VPN instance first and compare packets against the rule configured
with a VPN instance prior to other rules.
2)
If two rules are present with VPN instances, look at the protocol range in addition.
Then compare packets against the rule with the protocol carried on IP specified
prior to the other.