Trunk Links

Hi guys, I hope some one could help me out here

I have a small lab that includes two Cisco 2950 switches, I would like to wired up a 2nd link to create redundancy between them two, I want to be able to bundle both links right after using EtherChannel, I'm having problems connecting this two switches, I have no idea what type of cable to use either crossover which I think it is or straight through, or on which interface port should the 2nd Link be connected to, I just need the steps to connect both switches, I already know how to configured them after.

Thank you in advance gentlemen

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peanutnoggin

Elor0,

Crossover is the cable that you want to use. The switchport does not matter... it's good practice to be consistent. I usually use the first port on each switch and the last port as my redundant trunk. So... my config would like this:

SW1 - Fa0/1 ----crossover---- SW2 Fa0/1 (TRUNK)
SW1 - Fa0/12 ----crossover---- SW2 Fa0/12 (TRUNK)

HTH.

V/r

~Peanut

E1or0

Peanut Thank you for your advised, I will try it once I get home from work and I will let you know if it work for me, I tried that last time crossover on both links but the redundant link one of the switches was giving me an amber yellow light it never went to the forwarding mode ( green ), I guess is because I haven't configured that specific port for trunking ?, I'm currently working on my CCNA Exam so pls I ask some patience here

thank you once again peanut for your time

miller811

If spanning tree is running it will shut down the second link, since it will it see it a loop.

captobvious

miller811 wrote: »

If spanning tree is running it will shut down the second link, since it will it see it a loop.

+1 As well it should. You only need the redundant link if the first goes out.

E1or0

Miller that is so true, thanks for reminding me, I forgot about the SPT blocking that 2nd link avoiding a loop on the switch network, I'm still in the learning process here, before I was using packet tracer a lot, now that i have a pretty decent lab

I can really notice the side effects of any mistake

, a physical lab is the best thing to have for the exam,

peanutnoggin
miller811
captobvious

THANK YOU very much guys

E1or0

Grrr !!! I'm having a little problem setting up EtherChannel here...

Quick question gentlemen does trunk links have to be establish between switches first in order to use EtherChannel or not always? or on which circumstances is that you can perform EtherChannel for redundancy and increase the cost between switches, I have spent now like almost 5 hours trying to figure this out and I haven't been able to set up EtherChannel here yet

I think I'm giving up for the night, Will be back tomorrow though

Peanut
Correct me if I'm wrong, I think both redundant links between my two 2950 switches need to be in trunking mode to be able to set them up in EtherChannel, I just noticed that on the example you posted earlier, can you confirm if I'm right? Thanks

SW1 - Fa0/1 ----crossover---- SW2 Fa0/1 (TRUNK)<<

SW1 - Fa0/12 ----crossover---- SW2 Fa0/12 (TRUNK)<<

miller811

post the config from your switches so we can see what you are attempting to do.

elegua

E1or0 wrote: »

Grrr !!! I'm having a little problem setting up EtherChannel here... Quick question gentlemen does trunk links have to be establish between switches first in order to use EtherChannel or not always? or on which circumstances is that you can perform EtherChannel for redundancy and increase the cost between switches, I have spent now like almost 5 hours trying to figure this out and I haven't been able to set up EtherChannel here yet I think I'm giving up for the night, Will be back tomorrow though

Peanut
Correct me if I'm wrong, I think both redundant links between my two 2950 switches need to be in trunking mode to be able to set them up in EtherChannel, I just noticed that on the example you posted earlier, can you confirm if I'm right? Thanks

SW1 - Fa0/1 ----crossover---- SW2 Fa0/1 (TRUNK)<<
SW1 - Fa0/12 ----crossover---- SW2 Fa0/12 (TRUNK)<<

Configure the trunks and then etherchannel, i have it configured at home with 4 ports between 2 3550 and its working perfect, one thing that happened to me, i had to reload the switches to get the etherchannel up and running, try that and post the result.

3550-1#sh etherchannel port-channel 
                Channel-group listing: 
                ----------------------

Group: 1 
----------
                Port-channels in the group: 
                ---------------------------

Port-channel: Po1
------------

Age of the Port-channel   = 5d:03h:05m:51s
Logical slot/port   = 1/0          Number of ports = 4
GC                  = 0x00000000      HotStandBy port = null
Port state          = Port-channel Ag-Inuse 
Protocol            =    -
Port security       = Disabled

Ports in the Port-channel: 

Index   Load   Port     EC state        No of bits
------+------+------+------------------+-----------
  0     00     Fa0/21   On                 0
  0     00     Fa0/22   On                 0
  0     00     Fa0/23   On                 0
  0     00     Fa0/24   On                 0

Time since last port bundled:    5d:03h:05m:40s    Fa0/22

3550-1#

interface Port-channel1
 switchport trunk encapsulation dot1q
 switchport mode trunk

interface FastEthernet0/21
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet0/22
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet0/23
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 1 mode on
!
interface FastEthernet0/24
 switchport trunk encapsulation dot1q
 switchport mode trunk
 channel-group 1 mode on

Hope this help.

elegua

E1or0 wrote: »

Miller that is so true, thanks for reminding me, I forgot about the SPT blocking that 2nd link avoiding a loop on the switch network, I'm still in the learning process here, before I was using packet tracer a lot, now that i have a pretty decent lab

I can really notice the side effects of any mistake , a physical lab is the best thing to have for the exam,

peanutnoggin
miller811
captobvious

THANK YOU very much guys

If you configure etherchannel, STP sees them as a single interface (link) but if you only have 2 trunk ports them STP block one so, using etherchannel you are loop free and both up and running, i have 4 ports and all of then are in fwd state.

3550-1#sh spanning-tree 

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID    Priority    32769
             Address     000e.39ea.ae00
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32769  (priority 32768 sys-id-ext 1)
             Address     000e.39ea.ae00
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  300 sec

Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po1                 Desg FWD 8         128.65   P2p

3550-2#sh spanning-tree 

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID    Priority    32769
             Address     000e.39ea.ae00
             Cost        8
             Port        65 (Port-channel1)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32769  (priority 32768 sys-id-ext 1)
             Address     000f.234f.0300
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  300 sec

Interface           Role Sts Cost      Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po1                 Root FWD 8         128.65   P2p

check the last line on both switches, etherchannel is shows as Po1.

Hope this help.

E1or0

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Po1              Root FWD 12        128.65   P2p

Elegua you have been a life saver tonight...Thank you very much chief I didn't know I had to trunk both links in order to use EtherChannel, As soon I trunk both links at interfaces Fa0/1 and Fa0/2 and configured EtherChannel after to work on both interfaces, It bundle right away here are my stats

Switch2#sh interfaces port-channel 1 trunk

Port        Mode         Encapsulation  Status        Native vlan
Po1         on           802.1q         trunking      1

Port      Vlans allowed on trunk
Po1         1-4094

Port        Vlans allowed and active in management domain
Po1         1,20

Port        Vlans in spanning tree forwarding state and not pruned
Po1         1,20

Switch2#sh etherchannel port-channel
                Channel-group listing:
                -----------------------

Group: 1
----------
                Port-channels in the group:
                ----------------------

Port-channel: Po1
------------

Age of the Port-channel   = 00d:00h:26m:12s
Logical slot/port   = 1/0          Number of ports = 2
GC                  = 0x00000000      HotStandBy port = null
Port state          = Port-channel Ag-Inuse
Protocol            =    -

Ports in the Port-channel:

Index   Load   Port    EC state
------+------+------+------------
  0     00     Fa0/1    On/FEC
  0     00     Fa0/2    On/FEC

Time since last port bundled:    00d:00h:12m:36s    Fa0/1

elegua

Hi E1or0,

No problem bro, anytime.