Adding a Network ACL Rule (Default Priorities)

Scenarios

You can add inbound and outbound rules to a network ACL to control the traffic in and out of a subnet.

When you perform the following operations to add a rule, the system generates a priority based on the sequence when the rule is added. You cannot specify a priority.

As shown in Table 1, there are two custom inbound rules (rule A and rule B) and one default rule. The priority of rule A is 1 and that of rule B is 2. The default rule has the lowest priority. If rule C is added, the system sets its priority to 3, which has lower priority than rules A and B and higher priority than the default rule.

If the default priorities do not meet your requirements, you can customize the priorities by referring to Adding a Network ACL Rule (Custom Priorities).

Notes and Constraints

A network ACL can contain up to 100 rules in one direction, or performance will deteriorate.

Procedure

1. Log in to the management console.

2. Click in the upper left corner and select the desired region and project.
3. Click in the upper left corner and choose Networking > Virtual Private Cloud.

   The Virtual Private Cloud page is displayed.

4. In the navigation pane on the left, choose Access Control > Network ACLs.

   The network ACL list is displayed.

5. In the network ACL list, locate the target network ACL and click its name.

   The network ACL summary page is displayed.

6. On the Inbound Rules or Outbound Rules tab, click Add Rule.

   The Add Inbound Rule or Add Outbound Rule dialog box is displayed.

7. Configure required parameters.
   • Click to add more rules.
   • Locate the row that contains the network ACL rule and click Replicate in the Operation column to replicate an existing rule.

   Table 2 Parameter descriptions

   Parameter	Description	Example Value
   Type	Network ACL type. There are two options: IPv4 IPv6	IPv4
   Action	The action in the network ACL. There are two options: Allow: allows matched traffic in and out of a subnet. Deny: denies matched traffic in and out of a subnet.	Allow
   Protocol	The protocol supported by the network ACL to match traffic. The value can be TCP, UDP, or ICMP.	TCP
   Source	The source from which the traffic is allowed or denied. The source can be: IP address Single IP address: IP address/mask Example IPv4 address: 192.168.10.10/32 Example IPv6 address: 2002:50::44/128 IP address range in CIDR notation: IP address/mask Example IPv4 address range: 192.168.52.0/24 Example IPv6 address range: 2407:c080:802:469::/64 All IP addresses 0.0.0.0/0 represents all IPv4 addresses. ::/0 represents all IPv6 addresses. IP address group: The source is an IP address group. An IP address group is a collection of one or more IP addresses. You can select an available IP address group from the drop-down list. An IP address group can help you manage IP address ranges and IP addresses with same security requirements in a more simple way. Either the source or the destination of a network ACL rule can use the IP address group. For example, if the source uses an IP address group, the destination address cannot use an IP address group.	192.168.0.0/24
   Source Port Range	The source port or port range used to match traffic. The value ranges from 1 to 65535. Enter ports in the following format: Individual port: Enter a port, such as 22. Consecutive ports: Enter a port range, such as 22-30. Non-consecutive ports: Enter ports and port ranges, such as 22,24-30. You can enter a maximum of 20 ports and port ranges. Each port range must be unique. All ports: Leave it empty or enter 1-65535.	22-30
   Destination	The destination to which the traffic is allowed or denied. The destination can be: IP address Single IP address: IP address/mask Example IPv4 address: 192.168.10.10/32 Example IPv6 address: 2002:50::44/128 IP address range in CIDR notation: IP address/mask Example IPv4 address range: 192.168.52.0/24 Example IPv6 address range: 2407:c080:802:469::/64 All IP addresses 0.0.0.0/0 represents all IPv4 addresses. ::/0 represents all IPv6 addresses. IP address group: The destination is an IP address group. An IP address group is a collection of one or more IP addresses. You can select an available IP address group from the drop-down list. An IP address group can help you manage IP address ranges and IP addresses with same security requirements in a more simple way. Either the source or the destination of a network ACL rule can use the IP address group. For example, if the source uses an IP address group, the destination address cannot use an IP address group.	0.0.0.0/0
   Destination Port Range	The destination port or port range used to match traffic. The value ranges from 1 to 65535. Enter ports in the following format: Individual port: Enter a port, such as 22. Consecutive ports: Enter a port range, such as 22-30. Non-consecutive ports: Enter ports and port ranges, such as 22,23-30. You can enter a maximum of 20 ports and port ranges. Each port range must be unique. All ports: Leave it empty or enter 1-65535.	22-30
   Description	Supplementary information about the network ACL rule. This parameter is optional. The description can contain a maximum of 255 characters and cannot contain angle brackets (< or >).	N/A

8. Click OK.

   Return to the rule list to check the new rule.

   • The system generates priorities based on the sequence when rules are added. The rule that is added earlier is preferentially matched.
   • If the status of the new rule is Enabled, the rule is applied.