3750 stacking

francisco_1 · ‎07-02-2008

Is there any disadvanatages to stacking. or is there a reason why i should stack?

Mark Yeates · ‎07-02-2008

The only disadvantage I can think of is the distance you can have between the switches Via the stackwise cable. Stacking provides many advantages

1) 32 GB connection between switches in a stack. 64 for the E series.

2) one managed stack vs managing them all separately.

3) Need for less uplinks to the distribution layer.

4) great for future expansion.

Mark

ralphcarter · ‎07-02-2008

One other disadvantage is with the non-E series. When sending traffic between 2 hosts, the frame always enters the stack-ring. So if you have a stack of 6 switches and you have 2 hosts on the same exact switch in the stack, the frame still enters the stack-ring unnecessarily.

So if you are planning to run a stacked core or distribution go with 2 - 3 switches stacked max. The 3750s claim to support up to 48 etherchannels, but from my personal experience, the performance is not that great.

CCIE 26175
www.techsnips.com

Joseph W. Doherty · ‎07-02-2008

In addition to what the other posters have already noted, disadvantage of the stack, different IOS versions can not be run independently on different switches, nor can one switch be rebooted while possibly keeping the network up/hot with another switch.

Other advantages of the stack, possible avoidance of STP issues and multiple channels that can span stack members.

PS:

Also, on the non-E series, besides all packets being sent onto the stack rings whether necessary or not, it's also the source switch that removes the frame. I.e. all stack frames will hop across all stack links. Also, when the stack bandwidth is touted as 32 or 64 Mbps, realize there are two rings, so the effective bandwidth is half that noted, and second, the bandwidth is being doubled because it's full duplex, for example, on a non-E 3750, each stack connection is really 8 GBps, full duplex.