HP FlexNetwork NJ5000, User Manual

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ACL category Sequence of tie breakers
4.
Narrower TCP/UDP service port number range.
5.
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 number.
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.
Rule numbering
ACL rules can be manually numbered or automatically numbered. This section describes how
automatic ACL rule numbering works.
Rule numbering step
If you do not assign an ID to the rule you are creating, 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 creating,
they are automatically 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 takes the nearest higher multiple of the numbering step
to the current highest rule ID, starting with 0.
For example, if the numbering step is 5 (the default), and there are five ACL rules numbered 0, 5, 9,
10, and 12, the newly defined rule is numbered 15. If the ACL does not contain any rule, the first rule
is 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 causes the rules to be
renumbered 0, 2, 4, 6, and 8.
Implementing time-based ACL rules
You can implement ACL rules based on the time of day by applying a time range to them. A
time-based ACL rule takes effect only in any time periods specified by the time range.
The following basic types of time range are available:
•
Periodic time range
—Recurs periodically on a day or days of the week.