(Optional) Configuring a Secondary IP Address for an Interface
Context
Generally, an interface needs only a primary IP address. In some scenarios, you need to configure secondary IP addresses for an interface. For example, a switch connects to a physical network through an interface, and hosts on this network belong to two network segments. To enable the switch to communicate with all hosts on the physical network, configure a primary IP address and a secondary IP address for this interface. You can configure multiple IP addresses for a Layer 3 interface on a switch, one as the primary IP address, and the others as secondary IP addresses. Each Layer 3 interface can have a maximum of 31 secondary IP addresses.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number[.subinterface-number]
The interface view or sub-interface view is displayed.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support Ethernet sub-interfaces.
- Only hybrid and trunk interfaces on the preceding switches support Ethernet sub-interface configuration.
After you run the undo portswitch command to switch Layer 2 interfaces on the preceding series of switches into Layer 3 interfaces, you can configure Ethernet sub-interfaces on the interfaces.
After an interface is added to an Eth-Trunk, sub-interfaces cannot be configured on the interface.
- VLAN termination sub-interfaces cannot be created on a VCMP client.
- (Optional) On an Ethernet interface, run undo portswitch
The interface is switched to Layer 3 mode.
By default, an Ethernet interface works in Layer 2 mode.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support switching between Layer 2 and Layer 3 modes.
- Run ip address ip-address { mask | mask-length } sub
A secondary IP address is configured for the interface.
By default, no secondary IP address is configured for an interface.