Help Center/ Virtual Private Cloud/ User Guide/ Virtual IP Address/ Binding a Virtual IP Address to an Instance or EIP
Updated on 2024-08-07 GMT+08:00
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Binding a Virtual IP Address to an Instance or EIP

Scenarios

You can bind a virtual IP address to an instance or EIP. An instance can be an ECS, a network interface, or a Layer 2 connection.
  • Bind a virtual IP address to an instance. You can:
    • Bind one or more virtual IP addresses to an instance.
    • Bind a virtual IP address to multiple instances.
  • Bind a virtual IP address to an EIP to enable public network communication.

Notes and Constraints

It is recommended that a maximum of eight virtual IP addresses be bound to an ECS. If an ECS has multiple virtual IP addresses, each virtual IP address is used by a specific service. If there are too many services, the ECS may become overloaded and compromise user experience.

Binding a Virtual IP Address to an EIP or ECS on the Console

  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 Virtual Private Cloud > Subnets.

    The Subnets page is displayed.

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

    The subnet details page is displayed.

  6. On the IP Addresses tab, bind an EIP to the virtual IP address:
    1. Locate the row that contains the virtual IP address and click Bind to EIP in the Operation column.

      The Bind to EIP dialog box is displayed.

    2. Select an EIP and click OK.

      In the virtual IP address list, you can view that the virtual IP address has an EIP bound.

  7. On the IP Addresses tab, bind an instance to the virtual IP address:
    1. Locate the row that contains the virtual IP address and click Bind to Instance in the Operation column.

      The Bind to Instance dialog box is displayed.

    2. Select an instance and click OK.

      In the virtual IP address list, you can view that the virtual IP address has an instance bound.

Configuring a Virtual IP Address for an ECS

After you bind one or more virtual IP addresses to an ECS on the console, you must log in to the ECS to manually configure these virtual IP address.

The following OSs are used as examples here. For other OSs, see the help documents on their official websites.
  • Linux: CentOS 7.2 64bit and Ubuntu 22.04 server 64bit
  • Windows: Windows Server
The following uses CentOS 7.2 64bit as an example.
  1. Obtain the NIC that the virtual IP address is to be bound and the connection of the NIC:

    nmcli connection

    Information similar to the following is displayed:

    The command output in this example is described as follows:

    • eth0 in the DEVICE column indicates the NIC that the virtual IP address is to be bound.
    • Wired connection 1 in the NAME column indicates the connection of the NIC.
  2. Add the virtual IP address for the connection:

    nmcli connection modify "Connection name of the NIC" +ipv4.addresses Virtual IP address

    Configure the parameters as follows:

    • Connection name of the NIC: The connection name of the NIC obtained in 1. In this example, the connection name is Wired connection 1.
    • Virtual IP address: Enter the virtual IP address to be added. If you add multiple virtual IP addresses at a time, separate every two with a comma (,).
    Example commands:
    • Adding a single virtual IP address: nmcli connection modify "Wired connection 1" +ipv4.addresses 172.16.0.125
    • Adding multiple virtual IP addresses: nmcli connection modify "Wired connection 1" +ipv4.addresses 172.16.0.125,172.16.0.126
  3. Make the configuration in 2 take effect:

    nmcli connection up "Connection name of the NIC"

    In this example, run the following command:

    nmcli connection up "Wired connection 1"

    Information similar to the following is displayed:

  4. Check whether the virtual IP address has been bound:

    ip a

    Information similar to the following is displayed. In the command output, the virtual IP address 172.16.0.125 is bound to NIC eth0.

    To delete an added virtual IP address, perform the following steps:

    1. Delete the virtual IP address from the connection of the NIC:

      nmcli connection modify "Connection name of the NIC" -ipv4.addresses Virtual IP address

      To delete multiple virtual IP addresses at a time, separate every two with a comma (,). Example commands are as follows:
      • Deleting a single virtual IP address: nmcli connection modify "Wired connection 1" -ipv4.addresses 172.16.0.125
      • Deleting multiple virtual IP addresses: nmcli connection modify "Wired connection 1" -ipv4.addresses 172.16.0.125,172.16.0.126
    2. Make the deletion take effect by referring to 3.
The following uses Ubuntu 22.04 server 64bit as an example. If the ECS runs Ubuntu 22 or Ubuntu 20, perform the following operations:
  1. Obtain the NIC that the virtual IP address is to be bound:

    ifconfig

    Information similar to the following is displayed. In this example, the NIC bound to the virtual IP address is eth0. 
    root@ecs-X-ubantu:~# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.16.0.210  netmask 255.255.255.0  broadcast 172.16.0.255
        inet6 fe80::f816:3eff:fe01:f1c3  prefixlen 64  scopeid 0x20<link>
        ether fa:16:3e:01:f1:c3  txqueuelen 1000  (Ethernet)
        RX packets 43915  bytes 63606486 (63.6 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 3364  bytes 455617 (455.6 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
...
  2. Switch to the /etc/netplan directory:

    cd /etc/netplan

  3. Add a virtual IP address to the NIC.
    1. Open the configuration file 01-netcfg.yaml:

      vim 01-netcfg.yaml

    2. Press i to enter the editing mode.
    3. In the NIC configuration area, add a virtual IP address.

      In this example, add a virtual IP address for eth0:

      addresses:

      - 172.16.0.26/32

      The file content is as follows: 
      network:
    version: 2
    renderer: NetworkManager
    ethernets:
        eth0:
            dhcp4: true
            addresses:
            - 172.16.0.26/32
        eth1:
            dhcp4: true
        eth2:
            dhcp4: true
        eth3:
            dhcp4: true
        eth4:
            dhcp4: true
    4. Press Esc, enter :wq!, save the configuration, and exit.
  4. Make the configuration in 3 take effect:

    netplan apply

  5. Check whether the virtual IP address has been bound:

    ip a

    Information similar to the following is displayed. In the command output, the virtual IP address 172.16.0.26 is bound to NIC eth0. 
    root@ecs-X-ubantu:/etc/netplan# ip a
...
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether fa:16:3e:01:f1:c3 brd ff:ff:ff:ff:ff:ff
    altname enp0s3
    altname ens3
    inet 172.16.0.26/32 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet 172.16.0.210/24 brd 172.16.0.255 scope global dynamic noprefixroute eth0
       valid_lft 107999971sec preferred_lft 107999971sec
    inet6 fe80::f816:3eff:fe01:f1c3/64 scope link 
       valid_lft forever preferred_lft forever

    To delete an added virtual IP address, perform the following steps:

    1. Open the configuration file 01-netcfg.yaml and delete the virtual IP address of the corresponding NIC by referring to 3.
    2. Make the deletion take effect by referring to 4.

The following operations use Windows Server as an example.

  1. In Control Panel, click Network and Sharing Center, and click the corresponding local connection.
  2. On the displayed page, click Properties.
  3. On the Network tab page, select Internet Protocol Version 4 (TCP/IPv4).
  4. Click Properties.
  5. Select Use the following IP address and set IP address to the private IP address of the ECS, for example, 10.0.0.101.
    Figure 1 Configuring private IP address
  6. Click Advanced.
  7. On the IP Settings tab, click Add in the IP addresses area.

    Add the virtual IP address, for example, 10.0.0.154.

    Figure 2 Configuring virtual IP address
  8. Click OK.
  9. In the Start menu, open the Windows command line window and run the following command to check whether the virtual IP address has been configured:

    ipconfig /all

    In the command output, IPv4 Address is the virtual IP address 10.0.0.154, indicating that the virtual IP address of the ECS NIC has been correctly configured.

Helpful Links

Parent Topic: Virtual IP Address