Hi everyone.
Please consider the following example:
HOST1( 2.2.2.2)-----ge-0/0/0 -MX4--ge-0/0/1.100-------100.100.100.2 ( HSOT2, MAC:22:22:22:22:22:22)
Above MX4 is a router for host2, it uses irb.100 ( 100.100.100.100/24) to provide routing for host2.
1)Host1 sends a ping to 100.100.100.2, which is received by MX4 on ge-0/0/0.
2) MX4 finds this packet need to be routed out of irb.100, it therefore replace src mac with its mac associated with irb.100, and destination mac with 22:22:22:22:22:22 because MX4 finds the hosts2 mac in its arp table as shown below:
MX4> show arp
22:22:22:22:22:22 100.100.100.2 irb.100 [ge-0/0/1.100]
3) MX4 also finds host2 mac in its bridge mac table for vlan 100 as shown below:
root@MX4> show bridge mac-table
Routing instance : default-switch
Bridging domain : TEST, VLAN : 100
MAC MAC Logical NH MAC active
address flags interface Index property source
22:22:22:22:22:22 D ge-0/0/1.100
Question:
Will MX4 use arp table to forwards the packet out of ge-0/0/1.100 to host2 or will it use bridge mac table and forwards the frame out of ge-0/0/1.100 to host2?
Thanks and have a good weekend!!