Hello,
I am trying to connect a 2960 swith to 3560X using port channel. I have configred the switches with the following configratuion and connected them with straight ethernet cable, the link came up and then it went int err-disable state. I re-enabled the links and connected them using one cross over cable it connected and remained connected for a whole day in my lab. When I shut down both switches and took them the server room and connected both ports using cross over cable it came up and then went into err-disable state. Bellow is my configuration, can you please point out to me what I am missing: (no VTP domain configured on any of the switches)
------------------2960 configuration----------------------
interface Port-channel1
switchport trunk native vlan 999
switchport mode trunk
interface GigabitEthernet1/0/51
switchport trunk native vlan 999
switchport mode trunk
channel-group 1 mode on
interface GigabitEthernet1/0/52
switchport trunk native vlan 999
switchport mode trunk
channel-group 1 mode on
------------------3560X configuration-------------------------------
interface Port-channel1
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport mode trunk
interface GigabitEthernet0/23
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport mode trunk
channel-group 1 mode
interface GigabitEthernet0/24
switchport trunk encapsulation dot1q
switchport trunk native vlan 999
switchport mode trunk
channel-group 1 mode on
Thank you.
