Adding a Security Group Rule

Scenarios

A security group is a collection of access control rules to control the traffic that is allowed to reach and leave the cloud resources that it is associated with. The cloud resources can be cloud servers, containers, databases, and more. A security group consists of inbound and outbound rules.

If the rules of the security group associated with your instance cannot meet your requirements, for example, you need to allow inbound traffic on a specific TCP port, you can add an inbound rule to allow traffic on the TCP port.

Security Group Rule Configuration Examples

• Before configuring security group rules, you need to plan access policies for instances in the security group. For details about common security group rule configuration examples, see Security Group Configuration Examples.

Procedure

1. Log in to the management console.
2. Click in the upper left corner and choose Network > Virtual Private Cloud.

   The Virtual Private Cloud page is displayed.

3. In the navigation pane on the left, choose Access Control > Security Groups.

   The security group list is displayed.

4. Locate the row that contains the target security group, and click Manage Rule in the Operation column.

   The page for configuring security group rules is displayed.

5. On the Inbound Rules tab, click Add Rule.

   The Add Inbound Rule dialog box is displayed.

6. Configure required parameters.

   You can click + to add more inbound rules.

   Table 1 Inbound rule parameter description

   Parameter	Description	Example Value
   Type	Source IP address version. You can select: IPv4 IPv6	IPv4
   Protocol & Port	The network protocol used to match traffic in a security group rule. Currently, the value can be All, TCP, UDP, ICMP, or more.	TCP
   	Destination port used to match traffic in a security group rule. The value can be from 1 to 65535. Inbound rules control incoming traffic over specific ports to instances in the security group.	22, or 22-30
   Source	Source of the security group rule. The value can be an IP address or a security group to allow access from IP addresses or instances in the security group. For example: IP address: Single IP address: 192.168.10.10/32 (IPv4); 2002:50::44/128 (IPv6) All IP addresses: 0.0.0.0/0 (IPv4); ::/0 (IPv6) IP address range: 192.168.1.0/24 (IPv4); 2407:c080:802:469::/64 (IPv6) If the source is a security group, this rule will apply to all instances associated with the selected security group.	0.0.0.0/0
   Description	Supplementary information about the security group rule. This parameter is optional. The security group rule description can contain a maximum of 255 characters and cannot contain angle brackets (< or >).	N/A

7. Click OK.

   The inbound rule list is displayed.

8. On the Outbound Rules tab, click Add Rule.

   The Add Outbound Rule dialog box is displayed.

9. Configure required parameters.

   You can click + to add more outbound rules.

   Table 2 Outbound rule parameter description

   Parameter	Description	Example Value
   Type	Destination IP address version. You can select: IPv4 IPv6	IPv4
   Protocol & Port	The network protocol used to match traffic in a security group rule. Currently, the value can be All, TCP, UDP, ICMP, or more.	TCP
   	Destination port used to match traffic in a security group rule. The value can be from 1 to 65535. Outbound rules control outgoing traffic over specific ports from instances in the security group.	22, or 22-30
   Destination	Destination of the security group rule. The value can be an IP address or a security group to allow access to IP addresses or instances in the security group. For example: IP address: Single IP address: 192.168.10.10/32 (IPv4); 2002:50::44/128 (IPv6) All IP addresses: 0.0.0.0/0 (IPv4); ::/0 (IPv6) IP address range: 192.168.1.0/24 (IPv4); 2407:c080:802:469::/64 (IPv6)	0.0.0.0/0
   Description	Supplementary information about the security group rule. This parameter is optional. The security group rule description can contain a maximum of 255 characters and cannot contain angle brackets (< or >).	N/A

10. Click OK.

    The outbound rule list is displayed.

Verifying Security Group Rules

After required security group rules are added, you can verify whether the rules take effect. For example, if you have deployed a website on an ECS and want users to access your website through HTTP (80), you need to add an inbound rule to the ECS security group to allow access over the port. Table 3 shows the rule.

Linux ECS

Check whether the security group rule takes effect on a Linux ECS:

1. Log in to the ECS.
2. Run the following command to check whether TCP port 80 is being listened on:

   netstat -an | grep 80

   If information similar to Figure 1 is displayed, TCP port 80 is enabled.

   Figure 1 Command output for the Linux ECS
   
3. Enter http://ECS EIP in the address box of the browser and press Enter.

   If the requested page can be accessed, the security group rule has taken effect.

Windows ECS

To verify the security group rule on a Windows ECS:

1. Log in to the ECS.
2. Choose Start > Run. Type cmd to open the Command Prompt.
3. Run the following command to check whether TCP port 80 is being listened on:

   netstat -an | findstr 80

   If information similar to Figure 2 is displayed, TCP port 80 is enabled.

   Figure 2 Command output for the Windows ECS
   
4. Enter http://ECS EIP in the address box of the browser and press Enter.

   If the requested page can be accessed, the security group rule has taken effect.