HP HP 830 Series, Configuration Manual

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ACL category Sequence of tie breakers
IPv4 advanced ACL
3. Specific protocol type rather than IP (IP represents any protocol over IP).
4. More 0s in the source IP address wildcard mask.
5. More 0s in the destination IP address wildcard.
6. Narrower TCP/UDP service port number range.
7. Smaller ID.
IPv6 basic ACL
1. Longer prefix for the source IP address (a longer prefix means a narrower IP
address range).
2. Smaller ID.
IPv6 advanced ACL
1. Specific protocol type rather than IP (IP represents any protocol over IPv6).
2. Longer prefix for the source IPv6 address.
3. Longer prefix for the destination IPv6 address.
4. Narrower TCP/UDP service port number range.
5. Smaller ID.
Ethernet frame header ACL
1. More 1s in the source MAC address mask (more 1s means a smaller MAC
address).
2. More 1s in the destination MAC address mask.
3. Smaller ID.
A wildcard mask, also called an "inverse mask," is a 32-bit binary and represented in dotted decimal
notation. In contrast to a network mask, the 0 bits in a wildcard mask represent ‘do care’ bits, while the
1 bits represent 'don’t care bits'. If the 'do care' bits in an IP address identical to the 'do care' bits in an
IP address criterion, the IP address matches the criterion. All 'don’t care' bits are ignored. The 0s and 1s
in a wildcard mask can be noncontiguous. For example, 0.255.0.255 is a valid wildcard mask.
ACL rule numbering
ACL rule numbering step
If you do not assign an ID to the rule you are adding, the system automatically assigns it a rule ID. The
rule numbering step sets the increment by which the system automatically numbers rules. For example, the
default ACL rule numbering step is 5. If you do not assign IDs to rules you are adding, they are numbered
0, 5, 10, 15, and so on. The wider the numbering step, the more rules you can insert between two rules.
By introducing a gap between rules rather than contiguously numbering rules, you have the flexibility of
inserting rules in an ACL. This feature is important for a config order ACL, where ACL rules are matched
in ascending order of rule ID.
Automatic rule numbering and renumbering
The ID automatically assigned to an ACL rule uses the higher multiple of the numbering step that is
nearest to the current highest rule ID, starting with 0.
For example, if the numbering step is 5 (the default), and five ACL rules numbered 0, 5, 9, 10, and 12
exist, the newly defined rule will be numbered 15. If the ACL does not contain any rule, the first rule will
be numbered 0.
Whenever the step changes, the rules are renumbered, starting from 0. For example, if there are five rules
numbered 5, 10, 13, 15, and 20, changing the step from 5 to 2 renumbers the rules to 0, 2, 4, 6 and
8.