Cisco 6500 Etherchannel

[Salvador Antonio Quintanilla Mendoza]

Hi,

     I have configured a LACP etherchannel with 4 members (2 of this members are in a WS-SUP720-3B module and the other 2 members are in a WS-X6724-SFP module... the 4 ports are configured the same but the port-channel comes up like this: one pair are Po2 and the other Po2A.

Is this a valid configuration? use the 2 ports on the supervisor module to be part of an etherchannel?

show etherchannel sum
Flags:  D - down        P - bundled in port-channel
        I - stand-alone s - suspended
        H - Hot-standby (LACP only)
        R - Layer3      S - Layer2
        U - in use      N - not in use, no aggregation
        f - failed to allocate aggregator

        M - not in use, no aggregation due to minimum links not met
        m - not in use, port not aggregated due to minimum links not met
        u - unsuitable for bundling
        d - default port

        w - waiting to be aggregated
Number of channel-groups in use: 3
Number of aggregators:           4

Group  Port-channel  Protocol    Ports
------+-------------+-----------+-----------------------------------------------
1      Po1(SU)         PAgP      Gi1/12(P)      Gi1/15(P)
2      Po2(SU)         LACP      Gi1/21(P)      Gi1/22(P)
2      Po2A(SU)        LACP      Gi5/1(P)       Gi5/2(P)
11     Po11(SD)         -

[Joseph W. Doherty]

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Posting

The ports might have different QoS architectures.

Are you using "no mls qos channel-consistency"?

[Salvador Antonio Quintanilla Mendoza]

No, this is the configuration of the four ports.

!
interface GigabitEthernetx/x
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1-6,10,12-14,16,17,19-23,26,27,31,33,34,100
 switchport mode trunk
 switchport nonegotiate
 speed nonegotiate
 mls qos trust dscp
 channel-group 2 mode active
end

!

[Bilal Nawaz]

If you are sure 100% that the configuration is the same then I have question for you... Were interfaces gi5/x added in the port-channel after, at later date?

Please in maintenance window, shut the entire port channel down including its members on both sides, and bring them back up. Follow in these steps.

1) Delete the port-channel interface on both sides.

2) Re-create the port-channel

3) Put the members in port channel

4) Ensure the same configuration on port-channel and physical interfaces.

5) Check if matching similar config on other side

6) Bring up all interfaces including Po

hth

Bilal - CCIE #45032

[paul driver]

Hello Bilal

That's interesting -I would personally do a different approach here from you as regards steps 2 & 3

2) default the physical interfaces and shut them down
3) Assign the physical interfaces to a channel-group ( this automatically and cleanly creates the port-channel)

4) configure the port-channel which also embeds  that configuration to the physical interfaces

res

Paul
 

[Bilal Nawaz]

Hello Paul...

What I meant is this below with examples:

1) Delete the port-channel interface on both sides.

no int poX

2) Re-create the port-channel (we are in control, not the switch in control of us - we create the port-channel - just a mentality thing)

int po X

3) Put the members in port channel

interface gix/x

channel-group x mode active

4) Ensure the same configuration on port-channel and physical interfaces. (Meaning literally copy and paste config from the port-channel to the physical interfaces)

interface poX

switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1-6,10,12-14,16,17,19-23,26,27,31,33,34,100
 switchport mode trunk
 switchport nonegotiate
 speed nonegotiate
!

interface gix/x

switchport
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1-6,10,12-14,16,17,19-23,26,27,31,33,34,100
 switchport mode trunk
 switchport nonegotiate
 speed no negotiate
channel-group x mode active

5) Check if matching similar config on other side (if they are not, then yes recommend starting right from scratch and defaulting the interfaces)

show etherchannel summary

show run int poX

show run int gix/x

6) Bring up all interfaces including Po

int poX

no shut

int gix/x

no shut (if its still admin down)

your point no.4 - I've seen some cases where not all config applied on the port-channel is replicated down to the physical interfaces. Hence I never ever leave it to the switch to decide what goes on it and what doesn't. I hard configure po and physical interfaces to be same :)

[paul driver]

Hello

LOL
I have experienced the reverse- after the port-channel created and the physical interfaces are then configured , the router/switch shows the correct configuration but intermittent issues have arisen especially in L2 aggregation and not so much at L3

I suppose were on different  paths to the same result?

res

Paul
 

[Salvador Antonio Quintanilla Mendoza]

Hi, Thanks for your answer. The initial connection was two trunk between switches (one of them blocked by stp) in the slot 5, I shutdown the blocked port and configure the port-channel with the 2 ports on slot 1 and the other in the slot 5... once configured, I turned on the ports. As a final step just added the remaining port in slot 5.

During the validation of services all was working wel but with the port-channels marked as Po2 and Po2A.

I will try the configuration that you tell me and will let you know.

Thanks.