How to Configure IRB interfaces on a Juniper Switch | vQFX | EVE-NG

IRB (Integrated Routing and Bridging) is a virtual L3 interface attached to a VLAN, which is similar to SVI in Cisco. It acts as the L3 gateway for the devices associated with a specific VLAN.

Topology:

Configuration:

1. Create a VLAN by assigning a name and an ID.

root@JNP-SW-01# set vlans vlan10 vlan-id 10

2. Assign an interface to the VLAN created.
root@JNP-SW-01# set interfaces xe-0/0/8 unit 0 family ethernet-switching vlan members vlan10

3. Create the subnet for the VLAN's broadcast domain.

root@JNP-SW-01# set interfaces irb unit 10 family inet address 172.17.10.100/24

NOTE: unit 10 in the above command represents the vlan id 10.

4. Bind the L3 interface with the VLAN.

root@JNP-SW-01# set vlans vlan10 l3-interface irb.10

5.Commit the changes.
root@JNP-SW-01# commit


Verify the Configuration with the below commands. 
root@JNP-SW-01> show interfaces irb terse 
Interface               Admin Link Proto    Local                 Remote
irb                     up    up
irb.10                  up    up   inet     172.17.10.100/24

Confirm the connectivity between the hosts associated with vlan 10 and the gateway.
VPCS> show ip
NAME        : VPCS[1]
IP/MASK     : 172.17.10.1/24
GATEWAY     : 0.0.0.0
DNS         : 
MAC         : 00:50:79:66:68:03
LPORT       : 20000
RHOST:PORT  : 127.0.0.1:30000
MTU         : 1500

VPCS> ping 172.17.10.100
84 bytes from 172.17.10.100 icmp_seq=1 ttl=64 time=224.260 ms
84 bytes from 172.17.10.100 icmp_seq=2 ttl=64 time=114.060 ms
84 bytes from 172.17.10.100 icmp_seq=3 ttl=64 time=111.373 ms

root@JNP-SW-01> show ethernet-switching table 
MAC flags (S - static MAC, D - dynamic MAC, L - locally learned, P - Persistent static, C - Control MAC
SE - statistics enabled, NM - non configured MAC, R - remote PE MAC, O - ovsdb MAC)
Ethernet switching table : 2 entries, 2 learned
Routing instance : default-switch
Vlan        MAC                 MAC         Age    Logical       NH        RTR 
name        address             flags              interface     Index     ID
vlan10      00:50:79:66:68:03   D             -   xe-0/0/8.0     0         0       
vlan10      00:50:79:66:68:04   D             -   xe-0/0/7.0     0         0       

root@JNP-SW-01> show vlans 
Routing instance     VLAN name     Tag          Interfaces
default-switch       default       1        
default switch       vlan10        10           xe-0/0/7.0*                                                       
                                                xe-0/0/8.0*