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08-25-2020 05:26 AM - edited 08-25-2020 05:28 AM
Greetings community members,
We have two 10G ports in Cisco C9500-40X to configure for a particular server, which communicates with various devices connected to a few different VLANs. We don't want to allow all VLANs on those ports, and we want to create a port-channel to boost up the communication.
I've already configured each port separately - the configuration is exactly the same (1:1). Trunk allows particular VLANs only. Now, let's go to the port-channel configuration.
1. Do I have to configure trunk mode on port-channel even if it's been already been done for each port? If yes - I assume, I have to rewrite trunk allow list as well.
2. If I don't configure trunk mode on those 10G ports, and if I (first) configure my port-channel to be in trunk mode - will the trunk mode configuration go all the way down to each port after I've combined them into that port-channel? Will the trunk configuration be copied down to each physical port?
3. If the native VLAN is set to 1, do I have to specify native VLAN in the port-channel configuration?
4. Should I even include the native VLAN in the port-channel "trunk allow list" just in case?
Here's what I've got so far:
I think this configuration might work (I'm not able to test it at the moment), however, I think there might be a better approach.
Regards.
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08-25-2020 06:29 AM
High level it should work as expected - what is other side device ? is that support LACP ? if not make it mode on (instead of active)
new device should work as expected, incase if you come across any issue.

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08-25-2020 06:55 AM
Hello,
1. Do I have to configure trunk mode on port-channel even if it's been already been done for each port? If yes - I assume, I have to rewrite trunk allow list as well.
--> whatever you configure on the port channel is imherited by the member interfaces, so you don't need to configure each member interface individually
2. If I don't configure trunk mode on those 10G ports, and if I (first) configure my port-channel to be in trunk mode - will the trunk mode configuration go all the way down to each port after I've combined them into that port-channel? Will the trunk configuration be copied down to each physical port?
--> see 1
3. If the native VLAN is set to 1, do I have to specify native VLAN in the port-channel configuration?
--> No. Vlan 1 is the default Vlan, you don't need to specify it explicitly
4. Should I even include the native VLAN in the port-channel "trunk allow list" just in case?
--> No. As a matter of fact, you cannot allow or disallow Vlan 1 from a trunk. It is always there.
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08-25-2020 06:29 AM
High level it should work as expected - what is other side device ? is that support LACP ? if not make it mode on (instead of active)
new device should work as expected, incase if you come across any issue.

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08-25-2020 06:55 AM
Hello,
1. Do I have to configure trunk mode on port-channel even if it's been already been done for each port? If yes - I assume, I have to rewrite trunk allow list as well.
--> whatever you configure on the port channel is imherited by the member interfaces, so you don't need to configure each member interface individually
2. If I don't configure trunk mode on those 10G ports, and if I (first) configure my port-channel to be in trunk mode - will the trunk mode configuration go all the way down to each port after I've combined them into that port-channel? Will the trunk configuration be copied down to each physical port?
--> see 1
3. If the native VLAN is set to 1, do I have to specify native VLAN in the port-channel configuration?
--> No. Vlan 1 is the default Vlan, you don't need to specify it explicitly
4. Should I even include the native VLAN in the port-channel "trunk allow list" just in case?
--> No. As a matter of fact, you cannot allow or disallow Vlan 1 from a trunk. It is always there.
