question when doing etherchannel about a command in the cisco press | L2, L3

I see a pagp example with an additional option command.

it is a loadbalancing command but they do not explain this part, (src-mac | dst-mac.)

Also:

another question: ABOUT L2, L3

when I configure the etherchannel, supposedly when you add the commands switchport trunk, this should be a L3 cabability, yes?

But when I do a show etherchannel detail it reports L2.

I am using 2 3550 those are L3 switch's.

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Trifidw

A trunked link is still layer 2, just with the different VLANs tagged across the link. If you did no switchport and add a IP address to the link it would then be a layer 3 routed link.

inscom.brigade

interface port-channel 1

would be necassary for L3 but not L2

Trifidw

inscom.brigade wrote: »

I see a pagp example with an additional option command.

it is a loadbalancing command but they do not explain this part, (src-mac | dst-mac.)

PaGP and LACP are the protocols used to negotiate the etherchannel. The switch can then chose which method to load balance based on XOR logic on a variety of attributes from the frame, i.e. source mac address and destination mac address. Different switches can support more methods such as IP address and ports.

I don't understand what you're asking in the post above. Interface port-channel 1 is just a virtual interface that is created when you place up to 8 switchports into a group with the command channel-group 1 mode desirable.

MickQ

L2 is switching, remember? Trunk links are related to VLANS are related to ... switching! Hence, L2.

L3 is routing. You'll use the no switchport command to make the interfaces L3, group them into an etherchannel, and then apply an IP address, etc. as you desire for a routed etherchannel.

The "src mac | dst mac" are, as Trifidw said, the value entered into a bit hashing algorithm for loadbalancing. This is for L2.
For L3, you will have the options of source and destination IP. Once again, this is bit hash determined.

On the higher end switches (4500, 6500) you'll get the option of using ports.

The XOR algorithm takes place when you select the use of source and destination (mac/IP/port).

inscom.brigade

by using the router functionabilty in a Switch = L3 switching.

by entering commands like:

int vlan 10
ip add 10.0.0.1 0.0.0.0

int port-channel 1
ip add 10.0.1.2 0.0.0.0

These commands are L3, and thus using the router portion/features within a L3 switch.
is correct?

Zartanasaurus

inscom.brigade wrote: »

by using the router functionabilty in a Switch = L3 switching.

by entering commands like:

int vlan 10
ip add 10.0.0.1 0.0.0.0

int port-channel 1
ip add 10.0.1.2 0.0.0.0

These commands are L3, and thus using the router portion/features within a L3 switch.
is correct?

Are you activating router features in your computer when you assign an IP to the NIC?

xXErebuS

Trifidw wrote: »

PaGP and LACP are the protocols used to negotiate the etherchannel. The switch can then chose which method to load balance based on XOR logic on a variety of attributes from the frame, i.e. source mac address and destination mac address. Different switches can support more methods such as IP address and ports.

I don't understand what you're asking in the post above. Interface port-channel 1 is just a virtual interface that is created when you place up to 8 switchports into a group with the command channel-group 1 mode desirable.

Keep in mind the maximum amounts for ether-channel groups is hardware dependent.

MickQ

And also IOS version dependent.