Help Center/ Elastic IP/ FAQs/ EIP Binding and Unbinding/ Can Multiple EIPs Be Bound to an ECS?
Updated on 2024-04-09 GMT+08:00
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Can Multiple EIPs Be Bound to an ECS?

Scenarios

Multiple EIPs can be bound to an ECS, but this operation is not recommended.

If an ECS has multiple NICs attached and you want to bind multiple EIPs to this ECS, you need to configure policy-based routes for these NICs so that these extension NICs can communicate with external works. For details, see Configuration Example.

Configuration Example

Table 1 lists ECS configurations.

Table 1 ECS configurations

Parameter

Configuration

Name

ecs_test

Image

CentOS 6.5 64bit

EIP

2

Primary NIC

eth0

Secondary NIC

eth1

Example 1:

If you intend to access public network 11.11.11.0/24 through standby NIC eth1, perform the following operations to configure a route:
  1. Log in to the ECS.
  2. Run the following command to configure a route:

    ip route add 11.11.11.0/24 dev eth1 via 192.168.2.1

    In the preceding command, 192.168.2.1 is the gateway IP address of standby NIC eth1.

Example 2:

Based on example 1, if you intend to enable routing for default public network traffic through standby NIC eth1, perform the following operations to configure a route:

  1. Log in to the ECS.
  2. Run the following command to delete the default route:

    ip route delete default

    Exercise caution when deleting the default route because this operation will interrupt the network and result in SSH login failures.

  3. Run the following command to configure a new default route:

    ip route add 0.0.0.0/0 dev eth1 via 192.168.2.1

    In the preceding command, 192.168.2.1 is the gateway IP address of standby NIC eth1.