How to configure IRB(Integrated Routing and Bridging)

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[ Backgroud ]

PC1 is connected to Fa0/0(no IP address, bridge) of Router = IP 10.10.10.1/24
PC2 is connected to Fa0/1(no IP address, bridge) of Router = IP 10.10.10.2/24
PC3 is connected to Fa1/0(IP 20.20.20.1) of Router = IP 20.20.20.2/24
BVI is configured on Router = IP 10.10.10.3/24. (Gateway IP for PC1 and PC2)

Router#config t
Router(config)# bridge irb

Router(config)# bridge 100 protocol ieee
Router(config)# bridge 100 bridge ip
Router(config)# bridge 100 route ip

Router(config)# interface bvi
Router(config-if)# ip address 10.10.10.3 255.255.255.0

Router(config)# interface fa0/0
Router(config-if)# bridge group 100

Router(config)# interface fa0/1
Router(config-if)# bridge group 100

Router# sh int irb

FastEthernet0/0

 Routed protocols on FastEthernet0/0:
  ip      

 Bridged protocols on FastEthernet0/0:
  appletalk  clns       decnet     ip      

 Software MAC address filter on FastEthernet0/0
  Hash Len    Address      Matches  Act      Type
  0x00:  0 ffff.ffff.ffff         1 RCV Physical broadcast
  0x2A:  0 0900.2b01.0001         0 RCV DEC spanning tree
  0x6D:  0 cc09.6dcf.0000         4 RCV Interface MAC address
  0x6D:  1 cc09.6dcf.0000         0 RCV Bridge-group Virtual Interface
  0xC0:  0 0100.0ccc.cccc        29 RCV CDP
  0xC2:  0 0180.c200.0000         0 RCV IEEE spanning tree
  0xC2:  1 0180.c200.0000         0 RCV IBM spanning tree
  0xC2:  2 0100.0ccd.cdce         0 RCV VLAN Bridge STP

FastEthernet0/1

 Routed protocols on FastEthernet0/1:
  ip      

 Bridged protocols on FastEthernet0/1:
  appletalk  clns       decnet     ip      

 Software MAC address filter on FastEthernet0/1
  Hash Len    Address      Matches  Act      Type
  0x00:  0 ffff.ffff.ffff        12 RCV Physical broadcast
  0x2A:  0 0900.2b01.0001         0 RCV DEC spanning tree
  0x6C:  0 cc09.6dcf.0001         0 RCV Interface MAC address
  0x6D:  0 cc09.6dcf.0000        14 RCV Bridge-group Virtual Interface
  0xC0:  0 0100.0ccc.cccc        29 RCV CDP
  0xC2:  0 0180.c200.0000         0 RCV IEEE spanning tree
  0xC2:  1 0180.c200.0000         0 RCV IBM spanning tree
  0xC2:  2 0100.0ccd.cdce         0 RCV VLAN Bridge STP

FastEthernet1/0

 Routed protocols on FastEthernet1/0:
  ip      

BVI100

 Routed protocols on BVI100:
  ip      
Router#

 

Router# sh int bvi 100
BVI100 is up, line protocol is up
  Hardware is BVI, address is cc09.6dcf.0000 (bia cc09.6dcf.0000)
  Internet address is 10.10.10.3/24
  MTU 1500 bytes, BW 100000 Kbit, DLY 5000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output never, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/0 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     7 packets input, 690 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     28 packets output, 3084 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 unknown protocol drops
     0 output buffer failures, 0 output buffers swapped out
Router#

Router# sh bridge

Total of 300 station blocks, 298 free
Codes: P – permanent, S – self

Bridge Group 100:

    Address       Action   Interface       Age   RX count   TX count
cc0a.6dcf.0000   forward   FastEthernet0/1   0          5          5
cc05.6dcf.0000   forward   FastEthernet0/0   0          5          5
Router#