hi:
i am just new to cisco switchs and routers. i am running packet tracer and having a question about etherchannel redundancy.
my toplogy looks like below
i added both PCs to vlan 10 via port 10
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/9, Fa0/11, Fa0/12, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22
10 vlan010 active Fa0/10
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
and then i created trunk lines between two switches
Switch#show int trunk
Port Mode Encapsulation Status Native vlan
Fa0/23 on 802.1q trunking 1
Fa0/24 on 802.1q trunking 1
Po1 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/23 1-1005
Fa0/24 1-1005
Po1 1-1005
Port Vlans allowed and active in management domain
Fa0/23 1,10
Fa0/24 1,10
Po1 1,10
Port Vlans in spanning tree forwarding state and not pruned
Fa0/23 1,10
Fa0/24 1,10
Po1 1,10
after that i created an etherchannel on both switches
Switch#show etherchannel port-channel
Channel-group listing:
----------------------
Group: 1
----------
Port-channels in the group:
---------------------------
Port-channel: Po1
------------
Age of the Port-channel = 00d:01h:20m:52s
Logical slot/port = 2/1 Number of ports = 2
GC = 0x00000000 HotStandBy port = null
Port state = Port-channel
Protocol = PAGP
Port Security = Disabled
Ports in the Port-channel:
Index Load Port EC state No of bits
------+------+------+------------------+-----------
0 00 Fa0/24 On 0
0 00 Fa0/23 On 0
Time since last port bundled: 00d:00h:11m:51s Fa0/23
after that i created load-balance
Switch#show etherchannel load-balance
EtherChannel Load-Balancing Operational State (src-dst-mac):
Non-IP: Source XOR Destination MAC address
IPv4: Source XOR Destination MAC address
IPv6: Source XOR Destination MAC address
when i ran the "show spanning-tree" command the cost did become less than 19.
Switch#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0002.4A2A.144E
Cost 9
Port 25(Port-channel 1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0030.F265.1856
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 20
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Po1 Root FWD 9 128.25 Shr
VLAN0010
Spanning tree enabled protocol ieee
Root ID Priority 32778
Address 0002.4A2A.144E
Cost 9
Port 25(Port-channel 1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
and here is my question. i tried to test my
redundancy by sending ping continuesly from one pc to another .
however when i truned off the port 23, the ping was stopped and request time out .
if i resume port 23 and turned off port 24 everything goes like it should.
so why was this happened ? did i make mistake somewhere ? i throught etherchanel supports redundancy if one line goes down, the switch should pick up another immediately.
