[SW1] for p in eth0 eth1 eth2; do brctl delif br0 $p; brctl addif br0 $p; done; brctl showmacs br0
for p in eth0 eth1 eth2; do brctl delif br0 $p; brctl addif br0 $p; done; br
ctl showmacs br0
port no	mac addr		is local?	ageing timer
  1	02:42:1c:a3:43:00	yes		   0.00
  1	02:42:1c:a3:43:00	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
/ # 
/ # 

[SW1] ip link set eth1 down
ip link set eth1 down
/ # 
/ # 

[PC1] ping 192.168.10.20 -c 1 -i 500 -w 1000
ping 192.168.10.20 -c 1 -i 500 -w 1000

host (192.168.10.20) not reachable

VPCS> 

[SW1] brctl showmacs br0
brctl showmacs br0
port no	mac addr		is local?	ageing timer
  1	00:50:79:66:68:00	no		   3.22
  1	02:42:1c:a3:43:00	yes		   0.00
  1	02:42:1c:a3:43:00	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
/ # 
/ # 

[SW1] ip link set eth1 up
ip link set eth1 up
/ # 
/ # 

[PC1] ping 192.168.10.20 -c 3 -i 500 -w 1000
ping 192.168.10.20 -c 3 -i 500 -w 1000

84 bytes from 192.168.10.20 icmp_seq=1 ttl=64 time=1.436 ms
84 bytes from 192.168.10.20 icmp_seq=2 ttl=64 time=1.083 ms
84 bytes from 192.168.10.20 icmp_seq=3 ttl=64 time=1.155 ms

VPCS> 

[SW1] brctl showmacs br0
brctl showmacs br0
port no	mac addr		is local?	ageing timer
  1	00:50:79:66:68:00	no		   4.22
  2	00:50:79:66:68:01	no		   4.22
  1	02:42:1c:a3:43:00	yes		   0.00
  1	02:42:1c:a3:43:00	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  2	02:42:1c:a3:43:01	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
  3	02:42:1c:a3:43:02	yes		   0.00
/ # 
/ # 