cisco 3750 stacking or no

In my opinion - better work without stack- but it's important what you want to achive. If you use stack you have better meangemet because you have logically one unit. If not- you have better redundancy because if somthing wrong happen with one node, a backup node should work. Bartosz Gagat

Hi Tony,

Stacked devices are really a 2 edged sword, you can easily cut yourself unless you carefully think it all through.

On the Pro side, is that both 3750's are managed as if they were a single device, so it becomes easier to do certain things such as redundancy.

On the Con side is that you still need to replicate port functionality across both physical switches to achieve that redundancy.

A very rough parallel is something like a 6500 with replicated cards, you need to ensure you replicate EVERYTHING to gain FULL redundancy.

We use a number of stacked 3750's as it can be a good way to run them, but you have to remain aware the physical construction of the "bigger" logical device. None of our stacked 3750's are used in a serious replication environment, however all have some form of partial backup capability in their design. You just have to make sure you are not pushing the limits anywhere.

So if all you wish to do is make device management easier, then yes you save on using a port, however in that case you will not gain on redundancy.

Cheers............pk.

You should definitely stack them to simplify management and support.

As far as the uplinks go - keep both of them (configured as an Etherchannel) which has the following benefits: - redundancy for the switch ports, SFPs, and fibre between them - double the bandwidth - makes you look good to your boss as you are making good use of the available technology that he has paid for.

This is the last Etherchannel I configured, in case you haven't done one before:

At the core switch (stack of 3750s):

interface GigabitEthernet3/0/52 switchport trunk encapsulation dot1q switchport mode trunk channel-group 1 mode on

interface GigabitEthernet4/0/1 switchport trunk encapsulation dot1q switchport mode trunk channel-group 1 mode on

And at the Edge switch (stack of 3750s) on Floor 1:

interface GigabitEthernet1/0/1 switchport trunk encapsulation dot1q switchport mode trunk channel-group 1 mode on

interface GigabitEthernet4/0/1 switchport trunk encapsulation dot1q switchport mode trunk channel-group 1 mode on

When you add a link to an existing etherchannel, you get a few seconds down-time (can't remember precisely - maybe 30s) so you would have to plan a brief outage to setup each etherchannel.