Assigning an IP address to an interface

An interface can have one primary address and multiple secondary addresses.

Typically, you need to configure a primary IP address for an interface. If the interface connects to multiple subnets, configure primary and secondary IP addresses on the interface so the subnets can communicate with each other through the interface.

In an IRF fabric, you can assign an IP address to the management Ethernet port of each member in the management Ethernet port view of the master. Only the IP address assigned to the management Ethernet port of the master takes effect. After an IRF fabric split, the IP addresses assigned to the management Ethernet ports of the new masters (original subordinates) take effect. Then you can use these IP addresses to log in to the new masters for troubleshooting.

• An interface can have only one primary IP address. A newly configured primary IP address overwrites the previous one.

• You cannot assign secondary IP addresses to an interface that obtains an IP address through IP unnumbered, BOOTP, or DHCP.

• The primary and secondary IP addresses assigned to the interface can be located on the same network segment. Different interfaces on your device must reside on different network segments.

• After an IRF split, the routing information on the original master might not be updated immediately. As a result, the management Ethernet port of the original master cannot be pinged from the master (original subordinate) in another IRF fabric. To resolve the problem, wait until route synchronization between the devices is completed or enable NSR for the routing protocol. For information about NSR, see Layer 3—IP Routing Configuration Guide.

• The following commands are mutually exclusive. You can configure only one of these commands to assign an IP address to the management Ethernet port of the IRF master.

  • The ip address command with the irf-member member-id option that specifies the master.

  • The ip address command that does not contain the irf-member member-id option.

  • The mad ip address command.

  • The ip address dhcp-alloc command.

• Exclude the management Ethernet port of the master from being shut down if MAD is enabled in the IRF fabric. The port can be kept in up state when the MAD status transits to Recovery.

• You can assign interfaces IP addresses that have different masks but the same network address if ANDed with the shortest mask. For example, 1.1.1.1/16 and 1.1.2.1/24 have the same network address 1.1.0.0 if ANDed with 255.255.0.0. You can assign the IP addresses to two interfaces on the device. By default, users connected to the two interfaces cannot communicate with each other. For the users to communicate, you must configure common proxy ARP on the device. For more information, see "Configuring proxy ARP."

1. Enter system view.

   system-view

2. Enter interface view.

   interface interface-type interface-number

3. Assign an IP address to the interface.

   ip address ip-address { mask-length | mask } [ irf-member member-id | sub ]

   By default, no IP address is assigned to the interface.

   To assign an IP address to the management Ethernet port of an IRF member device, enter the master's management Ethernet port view and specify the irf-member member-id option.