Custom Search

SUBSCRIBE

SUBSCRIBE : 300 + Free Video Tutorials Programming (Python, golang, Julia), DevOps

Wednesday, August 6, 2014

How linux bridge broadcast ARP packets and works like a switch

1)
Create 3 namespaces, 3 veth pairs and a linux bridge


create_3_namespaces_and_1_bridge()
{
    echo "Creating namespace and bridge......"

    ###Create 3 Namespaces
    sudo ip netns add ns1
    sudo ip netns add ns2
    sudo ip netns add ns3

    ###Create Bridge
    sudo brctl addbr br-test
    sudo brctl stp br-test off
    sudo ip link set dev br-test up

    ###Create veth pairs tap1---br-tap1
    sudo ip link add tap1 type veth peer name br-tap1
    #Move tap1 to ns1
    sudo ip link set tap1 netns ns1
    #Add br-tap1 to bridge br-test
    sudo brctl addif br-test br-tap1
    #UP tap1   
    sudo ip netns exec ns1 ip link set dev tap1 up
    #UP br-tap1
    sudo ip link set dev br-tap1 up

    ###Create veth pairs tap2---br-tap2
    sudo ip link add tap2 type veth peer name br-tap2
    #Move tap2 to ns2
    sudo ip link set tap2 netns ns2
    #Add br-tap2 to bridge br-test
    sudo brctl addif br-test br-tap2
    #UP tap2
    sudo ip netns exec ns2 ip link set dev tap2 up
    #UP br-tap2
    sudo ip link set dev br-tap2 up

    ###Create veth pairs tap3---br-tap3
    sudo ip link add tap3 type veth peer name br-tap3
    #Move tap3 to ns3
    sudo ip link set tap3 netns ns3
    #Add br-tap3 to bridge br-test
    sudo brctl addif br-test br-tap3
    #UP tap3
    sudo ip netns exec ns3 ip link set dev tap3 up
    #UP br-tap3
    sudo ip link set dev br-tap3 up

    ###Assign IP
    #Assign IP to tap1  
    sudo ip netns exec ns1 ip addr add 10.1.1.4/24 dev tap1
    #Assign IP to tap2
    sudo ip netns exec ns2 ip addr add 10.1.1.5/24 dev tap2
    #Assign IP to tap3
    sudo ip netns exec ns3 ip addr add 10.1.1.6/24 dev tap3

    ###Test Ping
    sudo ip netns exec ns1 ping 10.1.1.5 -c 1

    if [ $? -eq 0 ]; then
        echo "Ping working from ns1 (10.1.1.4) to ns2 (10.1.1.5)"
        echo "Created namespace and bridge......"
    else
        echo "Failed to Create namespace and bridge......"
    fi
}

 

delete_3_namespaces_and_1_bridge()
{

    echo "Deleting namespace and bridge......"

    sudo ip netns del ns1
    sudo ip netns del ns2
    sudo ip netns del ns3
    sudo ip link set dev br-test down
    sudo brctl delbr br-test

    if [ $? -eq 0 ]; then
        echo "Deleted namespace and bridge......"
    else
        echo "Failed to delete namespace and bridge......"
    fi
}

create_3_namespaces_and_1_bridge
#delete_3_namespaces_and_1_bridge


* We don't need to add IP to the linux bridge.Bridge will act as a switch and broadcast the APR packets and make entries into the MAC table in the bridge, we can use the command "brctl showmacs " to see this table.

* When you ping from "tap1" in namespace "ns1" to "tap2" in namespace "ns2", "tap1" first send a ARP broadcast packet and and that packet will get received by bridge "br-test" via the interface "br-tap1", then the bridge will broadcast that ARP packet to all interfaces connected to that bridge, So the interface "tap2" get that packest via the interface "br-tap2", "tap1" will indentify that the destination IP is belongs to that interface and send a ARP ACK packet back to the interface "tap1". Once the "tap1" get that ARP ACK packet, that will populate the ARP table in the namespace "ns1" with IP and MAC entry. Then the ping (ICMP) packest are send from "tap1" to "tap2" based on the ARP table in the namespace "ns1", MAC table in the bridge "br-test" and ARP table in the "ns2".




2)
Capture ICMP and ARP packets from all veth interfaces


2a)
Capture ICMP and ARP packets from interface tap1 and br-tap1

#sudo ip netns exec ns1 tshark -i tap1 -f "icmp or arp"
#sudo tshark -i br-tap1 -f "icmp or arp"


2b)
Capture ICMP and ARP packets from interface tap2 and br-tap2

#sudo ip netns exec ns2 tshark -i tap2 -f "icmp or arp"
#sudo tshark -i br-tap2 -f "icmp or arp"


2c)
Capture ICMP and ARP packets from interface tap3 and br-tap3

#sudo ip netns exec ns3 tshark -i tap3 -f "icmp or arp"
#sudo tshark -i br-tap3 -f "icmp or arp"


3)
List ARP table of namespace ns1, ns2 and ns3 and Clear it


3a)
List ARP table

#sudo ip netns exec ns1 arp -n
Clear ARP table
#sudo ip netns exec ns1 arp -d


3b)
#sudo ip netns exec ns2 arp -n
#sudo ip netns exec ns2 arp -d


3c)
#sudo ip netns exec ns3 arp -n
#sudo ip netns exec ns3 arp -d


4)
Ping from ns1 (10.1.1.4) to ns2 (10.1.1.5)

#sudo ip netns exec ns1 ping 10.1.1.5

5)
5a)
5a,a)
Capture ICMP and ARP packets from interface tap1 and br-tap1

#sudo ip netns exec ns1 tshark -i tap1 -f "icmp or arp"

  1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4
  2   0.000103 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 10.1.1.5 is at ba:01:a4:54:24:50

  3   0.000106     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=1/256, ttl=64
  4   0.000158     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=1/256, ttl=64 (request in 3)
4   5   1.000704     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=2/512, ttl=64
5   6   1.000865     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=2/512, ttl=64 (request in 5)
6   7   2.003246     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=3/768, ttl=64
7   8   2.003495     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=3/768, ttl=64 (request in 7)
8   9   3.004683     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=4/1024, ttl=64
9  10   3.004873     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=4/1024, ttl=64 (request in 9)
10  11   4.006729     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=5/1280, ttl=64
11  12   4.006921     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=5/1280, ttl=64 (request in 11)
12  13   5.008408     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=6/1536, ttl=64
13  14   5.008551     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=6/1536, ttl=64 (request in 13)
 15   5.008641 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 Who has 10.1.1.4?  Tell 10.1.1.5
 16   5.008654 be:bb:98:99:fe:b1 -> ba:01:a4:54:24:50 ARP 42 10.1.1.4 is at be:bb:98:99:fe:b1

16  17   6.009508     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=7/1792, ttl=64
 18   6.009641     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=7/1792, ttl=64 (request in 17)
18  19   7.016597     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=8/2048, ttl=64
 20   7.016719     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=8/2048, ttl=64 (request in 19)

Notes:
* Interface "tap1"(be:bb:98:99:fe:b1) first Broadcast (send) an ARP packet to find MAC address associated with the IP 10.1.1.5. You can see it in line-1. You can see that, in that packet source MAC address is the MAC address of interface "tap1" and destination MAC address is None(Broadcast).
* In line-2, you can see that an ARP packet comes to Interface "tap1"(be:bb:98:99:fe:b1) from Interface "tap2"(ba:01:a4:54:24:50) and tells that the IP:10.1.1.5 is belongs to the interface "tap2"(ba:01:a4:54:24:50).You can see that, in that packet source MAC address is the MAC address of interface "tap2" and destination MAC address of interface "tap1".

* At this point, ARP table in the namespace "ns1" get populated with an entry of IP and MAC map, IP:10.1.1.5 and MAC:ba:01:a4:54:24:50. You can list ARP table in the namespace "ns1" with following command.

#sudo ip netns exec ns1 arp -n
Address                  HWtype  HWaddress           Flags Mask            Iface
10.1.1.5                 ether   ba:01:a4:54:24:50   C                     tap1

* In line-3, send ICMP request packet.In that packet source IP is 10.1.1.4 and destination IP is 10.1.1.5
* In line-4, receive ICMP reply packet.In that packet source IP is 10.1.1.5 and destination IP is 10.1.1.4

* In line-15, receive ARP request packet from interface "tap2"(ba:01:a4:54:24:50) and asking that, is the IP:10.1.1.4 belongs to the interface "tap1", if yes, send a ARP reply packet.In that packet source MAC is "tap2"(ba:01:a4:54:24:50) and destination MAC is "tap1"(be:bb:98:99:fe:b1)
* In line-16, send ARP reply packet and tells that the IP:10.1.1.4 is associated with interface "tap1"(be:bb:98:99:fe:b1).

* At this point, ARP table in the namespace "ns2" get populated with an entry of IP and MAC map, IP:10.1.1.4 and MAC:be:bb:98:99:fe:b1. You can list ARP table in the namespace "ns2" with following command.

#sudo ip netns exec ns2 arp -n
Address                  HWtype  HWaddress           Flags Mask            Iface
10.1.1.4                 ether   be:bb:98:99:fe:b1   C                     tap2

5a,b)
#sudo tshark -i br-tap1 -f "icmp or arp"

  1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4
  2   0.000077 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 10.1.1.5 is at ba:01:a4:54:24:50

  3   0.000082     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=1/256, ttl=64
  4   0.000132     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=1/256, ttl=64 (request in 3)
4   5   1.000699     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=2/512, ttl=64
  6   1.000836     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=2/512, ttl=64 (request in 5)
6   7   2.003234     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=3/768, ttl=64
  8   2.003465     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=3/768, ttl=64 (request in 7)
8   9   3.004677     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=4/1024, ttl=64
 10   3.004823     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=4/1024, ttl=64 (request in 9)
10  11   4.006724     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=5/1280, ttl=64
 12   4.006892     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=5/1280, ttl=64 (request in 11)
12  13   5.008405     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=6/1536, ttl=64
 14   5.008523     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=6/1536, ttl=64 (request in 13)
 15   5.008613 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 Who has 10.1.1.4?  Tell 10.1.1.5
 16   5.008631 be:bb:98:99:fe:b1 -> ba:01:a4:54:24:50 ARP 42 10.1.1.4 is at be:bb:98:99:fe:b1

16  17   6.009503     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=7/1792, ttl=64
 18   6.009613     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=7/1792, ttl=64 (request in 17)
18  19   7.016586     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=8/2048, ttl=64
 20   7.016691     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=8/2048, ttl=64 (request in 19)

5b)
shows a list of learned MAC addresses for bridge "br-test"

#sudo brctl showmacs br-test
port no    mac addr        is local?    ageing timer
  3    66:c3:81:40:76:8c    yes           0.00
  1    86:1f:a0:72:1c:ea    yes           0.00
  2    86:d2:d0:1b:af:9e    yes           0.00

* 1 --> br-tap1
* 2 --> br-tap2
* 3 --> br-tap3

Notes:
* Bridge "br-test" will broadcast first ARP packet (0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4) from the interface "tap1" via "br-tap1" to all other interfaces ("br-tap2" and "br-tap3") attached to the bridge. Please check packets captured from "tap2", "br-tap2" and "tap3", "br-tap3", You can see this ARP packets there.

5c)
5c,a)

Capture ICMP and ARP packets from interface tap2 and br-tap2
#sudo ip netns exec ns2 tshark -i tap2 -f "icmp or arp"

  1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4
  2   0.000037 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 10.1.1.5 is at ba:01:a4:54:24:50

  3   0.000068     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=1/256, ttl=64
  4   0.000099     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=1/256, ttl=64 (request in 3)
4   5   1.000731     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=2/512, ttl=64
5   6   1.000789     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=2/512, ttl=64 (request in 5)
6   7   2.003271     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=3/768, ttl=64
7   8   2.003321     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=3/768, ttl=64 (request in 7)
8   9   3.004730     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=4/1024, ttl=64
 10   3.004777     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=4/1024, ttl=64 (request in 9)
10  11   4.006775     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=5/1280, ttl=64
 12   4.006823     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=5/1280, ttl=64 (request in 11)
12  13   5.008434     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=6/1536, ttl=64
13  14   5.008479     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=6/1536, ttl=64 (request in 13)
 15   5.008568 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 Who has 10.1.1.4?  Tell 10.1.1.5
 16   5.008612 be:bb:98:99:fe:b1 -> ba:01:a4:54:24:50 ARP 42 10.1.1.4 is at be:bb:98:99:fe:b1

16  17   6.009529     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=7/1792, ttl=64
 18   6.009570     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=7/1792, ttl=64 (request in 17)
18  19   7.016606     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=8/2048, ttl=64
 20   7.016647     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=8/2048, ttl=64 (request in 19)

Notes:
* Line-1, interface "tap2"(ba:01:a4:54:24:50) receives a ARP packets which asks "Who has 10.1.1.5?  Tell 10.1.1.4"
* Line-2, interface "tap2"(ba:01:a4:54:24:50) sends a ARP reply packet which tells that the IP:10.1.1.5 is ours.

* Line-15, interface "tap2"(ba:01:a4:54:24:50) sends a ARP packets which asks "Who has 10.1.1.4?  Tell 10.1.1.5"
* Line-16, interface "tap2"(ba:01:a4:54:24:50) sends a ARP reply packet which tells that the IP:10.1.1.4 is belogs to the interface "tap1"(be:bb:98:99:fe:b1).

* At this point, ARP table in the namespace "ns2" get populated with an entry of IP and MAC map, IP:10.1.1.4 and MAC:be:bb:98:99:fe:b1. You can list ARP table in the namespace "ns2" with following command.

#sudo ip netns exec ns2 arp -n
Address                  HWtype  HWaddress           Flags Mask            Iface
10.1.1.4                 ether   be:bb:98:99:fe:b1   C                     tap2

5c,b)
#sudo tshark -i br-tap2 -f "icmp or arp"

  1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4
1   2   0.000042 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 10.1.1.5 is at ba:01:a4:54:24:50

  3   0.000071     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=1/256, ttl=64
  4   0.000105     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=1/256, ttl=64 (request in 3)
4   5   1.000724     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=2/512, ttl=64
  6   1.000797     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=2/512, ttl=64 (request in 5)
6   7   2.003267     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=3/768, ttl=64
  8   2.003329     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=3/768, ttl=64 (request in 7)
8   9   3.004703     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=4/1024, ttl=64
9  10   3.004784     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=4/1024, ttl=64 (request in 9)
10  11   4.006770     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=5/1280, ttl=64
11  12   4.006830     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=5/1280, ttl=64 (request in 11)
12  13   5.008430     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=6/1536, ttl=64
13  14   5.008486     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=6/1536, ttl=64 (request in 13)
 15   5.008578 ba:01:a4:54:24:50 -> be:bb:98:99:fe:b1 ARP 42 Who has 10.1.1.4?  Tell 10.1.1.5
 16   5.008614 be:bb:98:99:fe:b1 -> ba:01:a4:54:24:50 ARP 42 10.1.1.4 is at be:bb:98:99:fe:b1

16  17   6.009525     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=7/1792, ttl=64
 18   6.009577     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=7/1792, ttl=64 (request in 17)
18  19   7.016606     10.1.1.4 -> 10.1.1.5     ICMP 98 Echo (ping) request  id=0x4456, seq=8/2048, ttl=64
 20   7.016654     10.1.1.5 -> 10.1.1.4     ICMP 98 Echo (ping) reply    id=0x4456, seq=8/2048, ttl=64 (request in 19)

5d)
5d,a)
Capture ICMP and ARP packets from interface tap3 and br-tap3

#sudo ip netns exec ns3 tshark -i tap3 -f "icmp or arp"
1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4

Notes:
* Line-1, interface "tap3"(c2:73:bd:3a:bc:65) receives a ARP packet which asks "Who has 10.1.1.5?  Tell 10.1.1.4". and no reply packet since the IP:10.1.1.5 doesn't belongs to the interface "tap3"

5d,b)
#sudo tshark -i br-tap3 -f "icmp or arp"
1   0.000000 be:bb:98:99:fe:b1 -> Broadcast    ARP 42 Who has 10.1.1.5?  Tell 10.1.1.4

Notes:
* Line-1, interface "br-tap3"(66:c3:81:40:76:8c) receives a ARP packet which asks "Who has 10.1.1.5?  Tell 10.1.1.4". and no reply packet since the IP:10.1.1.5 doesn't belongs to the interface "br-tap3"

6)
6a)
Interface Configuration of veth pairs tap1 and br-tap1


#sudo ip netns exec ns1 ifconfig tap1
tap1      Link encap:Ethernet  HWaddr be:bb:98:99:fe:b1 
          inet addr:10.1.1.4  Bcast:0.0.0.0  Mask:255.255.255.0
          inet6 addr: fe80::bcbb:98ff:fe99:feb1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:58 errors:0 dropped:0 overruns:0 frame:0
          TX packets:43 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4836 (4.8 KB)  TX bytes:3630 (3.6 KB)

#ifconfig br-tap1
br-tap1   Link encap:Ethernet  HWaddr 86:1f:a0:72:1c:ea 
          inet6 addr: fe80::841f:a0ff:fe72:1cea/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:43 errors:0 dropped:0 overruns:0 frame:0
          TX packets:58 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:3630 (3.6 KB)  TX bytes:4836 (4.8 KB)

6b)
Interface Configuration of veth pairs tap2 and br-tap2


#sudo ip netns exec ns2 ifconfig tap2
tap2      Link encap:Ethernet  HWaddr ba:01:a4:54:24:50 
          inet addr:10.1.1.5  Bcast:0.0.0.0  Mask:255.255.255.0
          inet6 addr: fe80::b801:a4ff:fe54:2450/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:54 errors:0 dropped:0 overruns:0 frame:0
          TX packets:35 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4484 (4.4 KB)  TX bytes:3014 (3.0 KB)

#ifconfig br-tap2
br-tap2   Link encap:Ethernet  HWaddr 86:d2:d0:1b:af:9e 
          inet6 addr: fe80::84d2:d0ff:fe1b:af9e/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:35 errors:0 dropped:0 overruns:0 frame:0
          TX packets:54 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:3014 (3.0 KB)  TX bytes:4484 (4.4 KB)

6c)
Interface Configuration of veth pairs tap3 and br-tap3


#sudo ip netns exec ns3 ifconfig tap3
tap3      Link encap:Ethernet  HWaddr c2:73:bd:3a:bc:65 
          inet addr:10.1.1.6  Bcast:0.0.0.0  Mask:255.255.255.0
          inet6 addr: fe80::c073:bdff:fe3a:bc65/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:33 errors:0 dropped:0 overruns:0 frame:0
          TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2566 (2.5 KB)  TX bytes:1222 (1.2 KB)

#ifconfig br-tap3
br-tap3   Link encap:Ethernet  HWaddr 66:c3:81:40:76:8c 
          inet6 addr: fe80::64c3:81ff:fe40:768c/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:15 errors:0 dropped:0 overruns:0 frame:0
          TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1222 (1.2 KB)  TX bytes:2566 (2.5 KB)

6d)
Interface Configuration of bridge br-test


#ifconfig br-test

br-test   Link encap:Ethernet  HWaddr 66:c3:81:40:76:8c 
          inet6 addr: fe80::1ca2:7eff:fe1e:51a2/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:24 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1476 (1.4 KB)  TX bytes:648 (648.0 B)




1 comment: