I have little prior experience dealing with stacking 3750s and was looking for a little help.
We have 18 fiber pairs collapsed from the IDFs at the distribution layer and I'm looking for the most cost effective way to handle this. I figured I would stack 2- 3750G-12S to handle the fiber and then run a 2 gig channel between the 3750 stack and the core switch which is a 3750G-24-TS. Is this feasible and could I stack all 3 (Distribution switches and core) together and avoid the 2 extra SFP modules and fiber patch cables between the distribution and core?
Thanks in advance..
Torbjorn proposes an interesting variation, using just a stack of copper 3750Gs and their SFP ports in lieu of any 3750G-12S models. However, to cover loss of any one 3750 I believe you would need a stack of 6, since otherwise a stack of 5 with a failed unit would leave you only 16 SFP ports and your original post did mention you have 18 fiber pairs.
Torbjorn also describes otherwise needing 3 3750G-12S models and 2 3750G-24TS-1U models. To support your 18 fiber ports, a stack of just 2 of each model (or 3750G-24TS in lieu of the 3750G-24TS-1U) should suffice. Failure of a 3750G-12S would still provide 20 SFP ports (12 + 4 + 4).
Rereading Torbjorn's post, he does mention having a spare 3750G-24TS-1U, for lab usage and on-hand spare, which provides the extra SFP ports you'll need. (My apologies to Torbjorn for missing this.)
Robert, since using 3750s is new to you, if you stack the distribution and core, I want to recap your options for supporting 24 copper and 18 fiber ports.
Without extra ports to cover loss of a 3750, you can stack:
2 3750G-12S and 1 3750G-24TS(or -U)
1 3750G-12S and 2 3750G-24TS(or -U)
5 3750G-24TS(or -U)
Extra ports to cover loss of any one 3750 are provided by:
2 3750G-12S and 2 3750G-24TS(or -U)
6 3750G-24TS(or -U)
For 3750 failure replacement avoiding the need to repatch and reconfigure ports:
3 3750G-12S and 2 3750G-24TS(or -U)
6 3750G-24TS(or -U)
Torbjorn's suggestion offers the major advantages of lost of a 3750 shouldn't take out as many active ports assuming you've distributed them across the stack. Second, if you want to swap the failed unit with the spare without reconfiguration (NB: there are some prerequisites to doing this), you only need 1 more 3750 vs. the mixed type of 3750s providing the same ability.
You didn't note what you were planning to use as your routing protocol, if any. When pricing units, take careful note of what feature set is being priced.