LACP neighbor can't establish between 3850 and 2960X

[zexinfinite]

Hi all,

I've tried to establish LACP neighbor between 3850 and 2960X, but I can't see the LACP relationship come up. 

The LACP counter on 3850 is normal, there have send and receive LACPDU, but there have no receive packet on 2960X, even I tried to debug lacp all on 2960X and restart interface on 3850, there still can not receive LACPDU from Gi2/0/49 on 2960X.

I saw there have bug on 3.7.4，and already fixed on 3.7.5.

If it is possible to meet the bug again on these version?

# IOS version on 3850-24XS-E

Cisco IOS Software, IOS-XE Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 03.07.05.E RELEASE SOFTWARE (fc1)

#Config on 3850

interface Port-channel8
switchport trunk allowed vlan 123
switchport mode trunk
!

interface TenGigabitEthernet1/0/8
switchport trunk allowed vlan 123
switchport mode trunk
channel-group 8 mode active

!

interface TenGigabitEthernet2/0/8
switchport trunk allowed vlan 123
switchport mode trunk
channel-group 8 mode active

#show lacp counter on 3850
LACPDUs Marker Marker Response LACPDUs
Port Sent Recv Sent Recv Sent Recv Pkts Err
---------------------------------------------------------------------
Channel group: 8
Te1/0/8 59 60 0 0 0 0 0
Te2/0/8 226 58 0 0 0 0 0 

#IOS version on 2960X-48TS & 2960X-48FPS

Cisco IOS Software, C2960X Software (C2960X-UNIVERSALK9-M), Version 15.2(2)E6, RELEASE SOFTWARE (fc1)

#Config on 2960X

interface Port-channel1
description "To DG5 Distribution switch"
switchport trunk allowed vlan 123
switchport mode trunk
spanning-tree portfast disable
spanning-tree bpdufilter disable
spanning-tree bpduguard disable
spanning-tree guard none
ip dhcp snooping trust

!

interface GigabitEthernet1/0/49
description "To DG5 Distribution switch"
switchport trunk allowed vlan 123
switchport mode trunk
spanning-tree portfast disable
spanning-tree bpdufilter disable
spanning-tree bpduguard disable
spanning-tree guard none
channel-group 1 mode active
ip dhcp snooping trust

!

interface GigabitEthernet2/0/49
switchport trunk allowed vlan 123
switchport mode trunk
spanning-tree portfast disable
spanning-tree bpdufilter disable
spanning-tree bpduguard disable
spanning-tree guard none
channel-group 1 mode active
ip dhcp snooping trust

# show lacp counter on 2960X

LACPDUs Marker Marker Response LACPDUs
Port Sent Recv Sent Recv Sent Recv Pkts Err
---------------------------------------------------------------------
Channel group: 1
Gi1/0/49 83 77 0 0 0 0 0
Gi2/0/49 90 0 0 0 0 0 0

[Moses Fernandes]

Hello,

Make sure that ALL the port participating in the etherchannel have identical settings.

This includes speed, Vlans, Swichport mode.

You may also run --> sh interface Port-channel XX <--  on both the switches and compare the output.

You may also set the etherchannel to Active-Active and see if that helps.. 

If you find a post helpfull mark it as help full.

Regards,

Moses.

[zexinfinite]

Hi Moses,

Thank you for your opinion!

I've tried to reload second 3850 and it's work now.

[Julio E. Moisa]

Hi

Also check the negotiation, speed and duplex the same for both.