two layer 3 switch

[zorrs.fanai]

hello,

can anyone tell me the benefit of using two layer 3 switch in a network. does it reduce the cpu load and network faster or just for redundant. can anyone please tell me or give me some link where i can find such topic.

thank you 

[Jon Marshall]

The primary reason is for redundancy, so in a classic design each access layer switch would connect to two L3 switches which do all the routing for the vlans etc. 

More recent designs use stacking but still you have multiple switches in a stack. 

Jon

[Dennis Mink]

It depends, but generally adding a L3 switch is more likely to be about redundancy. if you are considering this you are best off using a 2 switch stack that is L3 capable so you can easily run port channels into it. but again, it depends on your requirements

[Joseph W. Doherty]

As Jon and Dennis have already noted, it's probably mostly done to provide redundancy, and as they have also noted, today it might be done more with a L3 stack of switches, operating as one logical switch, rather than multiple L3 switches operating independently (NB: there's pros and cons for both approaches).

Most L3 switches do not have CPU issues, as data plane traffic forwarding is generally supported by dedicated hardware (ASICs) in the switch. (Many current Enterprise switches can support full wire-speed on all their ports, concurrently.)

Having multiple L3 switches, depending on your design, might increase overall capacity. However. unless you're hitting capacity limits of one switch, unlikely a second switch would make your network "faster", as least as to you might perceive.