what is difference between Switch stacking, etherchannel? Can anyone e

[jobsp90]

If there are 2 switches stacked uplinks given to each 2 switches with 2 ports each, say eg port 47 & 48.Port 47 & 48 are created LACP for each switch Then what is the use of stacking here for redundancy?I am newbie. Please explain.

[marce1000]

   - Native stacking , is used to present a number of switches as a single entity ;  LACP has other purposes too , such as providing 'channeled links' to remote devices or other switches ,

 M.

[jobsp90]

Can u pls answer to my question based on the scenario.

[marce1000]

  - Then you need to provide the switch model(s)   , (both if they are different)

 M.

[13jobsp90]

stacked switch model is 2960x catalyst both are same switch model.

[marce1000]

   - For stacking 2960x devices  checkout : https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/stack_manager/configuration_guide/b_stck_152ex_2960-x_cg/b_stck_152ex_2960-x_cg_chapter_010.html

 M.

[Giuseppe Larosa]

Hello @jobsp90 ,

higher end switches like Cat 3750 , Cat 3850 and current Cat  9300 or higher support port-channels with members links distributed on multiple stack members this is called MEC  in Cisco terms   a more neutral name for this feature is MLAG.

Member switches appear a single box to the outside world in the management plane but also in the control plane ( for example for STP protocol). The models that support MEC or MLAG provides the additional capacity to create LACP port-channels that can survive to a single stack member complete failure.

In this way, actualy no STP topology change is triggered and user traffic is spread across the surviving members. Only end user devices that are single homed to the dead member are affected.

When used as indipendent devices, all the switches act as different STP devices so when one of them fails STP needs to recompute a loop free topology for all VLANs.

In the case of Cat 2960X according to the link provided by @marce1000 only the MEC or MLag is missing but you can still have some benefits from the use of a stack.

Hope to help

Giuseppe

[13jobsp90]

See both the switches are having uplink with 2 ports each. ok. So now the server is connected to both the switches, so in my scenario if I don't provide stacking and 1 switch goes down, but the servers will work in the secondary switch right?So here there is no need of stacking?Right?

[balaji.bandi]

Stack make 2 Physical device in to one Virtual Switch, so one Switch act as Master and other one will be Stanby or member to become active when master switch fails, (there are some requirement to make this work - high level you need to have same model of the switches to make it stacking - look at the product reference for stacking guide lines)

When you have different model of the switches ( or different vendors) you can make as stacking , so in this scenario you Looking to extended Layer 2, the Port Bundling you can use.

Again these all depends on what you looking to achive as a high availability and there are pros and cons, depends on the end device support.

[13jobsp90]

So my doubt is I what is the need for stacking here other than acting as a single unit. For redundancy?

[marce1000]

  - You don't have port-redundancy on a stack for single connected hosts , as usually. In stacking terms there is some kind of redundancy because you won't have an overall box failure , bringing everything down (e.g.) , only a single stack member can fail , besides extreme and or usual external circumstances , 

 M,

[13jobsp90]

if 1 switch goes down then another switch is there without stacking since it is also connected with another  uplink.

[marce1000]

  >..if 1 switch goes down then another switch is there without stacking since it is also connected with another  uplink.
                 It's better to say : any stack member remains in that role ,even if becoming single 
                 Uplinks are used for other purposes , such as connecting a client switch to the core network, 

 M.

[13jobsp90]

my question is if i dont give stacking but the 2 switches are given uplink for each switch. server is also connected in both the switches.then if 1 switch fails will the switch work.

[balaji.bandi]

As i mentioned depends on requirement, what you trying to solve the issue by designing the system

considering  Raliability, scalability, Availability, Configuration

My Notes from my blog - use case differs.

Stacking vs. LACP: What Is the Difference?

• LACP cannot bundle links across multiple switches. It can only bundle links within a single ethernet switch for increased bandwidth and redundancy. The primary purpose is to improve link-level reliability. To establish an aggregated connection between switches A, B, and C, you must enable LACP on specific ports on each switch and make physical connections.

• Stacking technology allows for bundling multiple switches to act as a single logical switch, to increase equipment-level reliability. Those switches are directly connected by stacking cable for stack link.