We're replacing legacy switches with 3750s in the coming months, and I have a question about stacking and port channel.
The 3750s will be Layer 2 switches, and each will be uplinked via Gigabit fiber to a pair of 6500s acting as Layer 3 distribution switches.
One thing I'm not sure about is if it will be possible to built Port Channel links for 2, 3, or 4 GB across different switches, or if I can only put Port Channels on the same switch. My understanding is with stacking it appears as one big switch and I can built Port Channels however I want, but am not 100% if this design will work.
You can certainly configure EtherChannels across different 3750s in the same stack, thus avoiding your single point of failure by having the aggregate ports all in one switch.
However in the scenario the port channel has to be configured explicitly to ON, PaGP is not supported across stack members.
3750 stack switches appear as a single logical switch with a single management address. From which you can configure all physical ports. It is important to remember that you configure your switch priorities accordingly in order to govern which switch is your master, and also set a secondary.
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