Supported Platforms
Configuring Integrated Routing and Bridging Interfaces (CLI Procedure)
Integrated routing and bridging (IRB) interfaces allow an EX Series switch to recognize packets that are being sent to local addresses so that they are bridged (switched) whenever possible and are routed only when necessary. Whenever packets can be switched instead of routed, several layers of processing are eliminated.
An interface named irb functions as a logical router on which you can configure a Layer 3 logical interface for each virtual LAN (VLAN). For redundancy, you can combine an IRB interface with implementations of the Virtual Router Redundancy Protocol (VRRP) in both bridging and virtual private LAN service (VPLS) environments.
Jumbo frames of up to 9216 bytes are supported on an IRB interface. To route jumbo data packets on the IRB interface, you must configure the jumbo MTU size on the member physical interfaces of the VLAN that you have associated with the IRB interface, as well as on the IRB interface itself (the interface named irb).
 | Caution: Setting or deleting the jumbo MTU size on the IRB interface (the interface named irb) while the switch is transmitting packets might result in dropped packets. |
To configure the IRB interface:
- Create a Layer 2 VLAN by assigning it a name and
a VLAN ID:
[edit]
user@switch# set vlans vlan-name vlan-id vlan-id - Assign an interface to the VLAN by naming the VLAN as
a trunk member on the logical interface, thereby making the interface
part of the VLAN’s broadcast domain:
[edit]
user@switch# set interfaces interface-name unit logical-unit-number family ethernet-switching vlan members vlan-name - Create a logical Layer 3 IRB interface (its name
will be irb.logical-interface-number, where the
value for logical-interface-number is the value
you supplied for vlan-id in Step 1; in the following
command, it is the logical-unit-number) on a
subnet for the VLAN’s broadcast domain:
[edit]
user@switch# set interfaces irb unit logical-unit-number family inet address inet-address - Link the Layer 2 VLAN to the logical Layer 3
IRB interface:
[edit]
user@switch# set vlans vlan-name l3-interface irb.logical-interface-number
Note: Layer 3 interfaces on trunk ports allow the interface to transfer traffic between multiple Layer 2 VLANs. Within a VLAN, traffic is switched, while across VLANs, traffic is routed.
