I am trying to setup a network that includes an EtherChannel link between two Cisco Layer 3 switches (Catalyst 3750). I am using a collapsed core hierarchical network.
The picture above is my topology. On my layer 2 access switches (S1, S2, S3) I have several hosts connected right now, on several VLANs.
My issue tho is that a host on for example S2, can't communicate with L3-1 through the EtherChannel between L3-1 and L3-2. I've tried making it a Layer 3 EtherChannel with IP's, and I can ping across, but it's like it wont propagate my tagged VLAN traffic.
**Example**:
> I connect HOST-A to L3-1 on interface GigabitEthernet2/0/1.
>
> I make GigabitEthernet2/0/1 switchport access on VLAN 20.
>
> HOST-B is connected to a switchport access VLAN 20 port on S2.
>
> HOST-B tries to ping L3-2. Succesful.
>
> HOST-B tries to ping across to L3-1 / HOST-A. Not succesful.
PS. I also have HSRP setup on the Layer 3 switches, for all my VLANs. Also I have a Main Windows Server 2016 Domain Controller connected to L3-1 and a Backup connected to L3-2.
Let me know if you need the IP scope.
I appreciate all help! I just want to know what I have to think of/be sure of is working, to make this network communicate. Any help that can guide me to what i can do to get traffic all the way to the WAN, and so that my hosts on S1, S2 and S3 can connect to the internet. Much appreciated.
**CONFIGURATION:**
L3-1
Port-Channel:
!
interface Port-channel1
no switchport
ip address 172.16.0.1 255.255.255.252
!
!
interface GigabitEthernet2/0/19
no switchport
no ip address
channel-group 1 mode desirable
!
interface GigabitEthernet2/0/20
no switchport
no ip address
channel-group 1 mode desirable
!
**L3-2 has same configuration on same ports and channel-group. It's IP address is 172.16.0.2 255.255.255.252 instead.**
VLAN-config:
All links between layer-3 and layer-2 switches are trunks. A snippet from L3-2:
**S1**
VLAN-config:
**S2**
VLAN-config:
**S3**
VLAN-config:
