How to find the Layer 3 switch is working fine or not?

Other intelligence commonly found in Layer 3 switches, includes the ability to logically segment a network into two or more Virtual LANs (VLANs) plus enhanced security controls to prevent unauthorised setup changes. Facilities to prioritise different types of traffic are also commonplace, to provide guaranteed Quality of Service (QoS) when, for example, building converged voice and data networks.

Layer 3 issues

Extra processing power is required to retrieve and make use of Layer 3 information. As a result, early switches could cause bottlenecks; nowadays, most Layer 3 switches operate at full wire speed just like their Layer 2 counterparts.

Prices are higher than for a Level 2 switch because extra processing power and memory is required for Layer 3 switching. Such switches also require setup and management. Most are configured via a Web based GUI, although support for the Simple Network Management Protocol (SNMP) is another common option.

Layer 3 switches can be complex to manage, especially on large distributed networks, but the concepts aren't that difficult and affordable Layer 3 switches are now available for small business deployment.

Which switch?

Small networks can be built using just Layer 2 devices, but most corporate networks will have a mix of Layer 2 and Layer 3 switches. Dumb Layer 2 products are a cheap and easy way of providing connectivity to workgroups while more intelligent Layer 3 switches enable departmental networks to be segmented and controlled with no loss of bandwidth.

Finally, it's worth noting that some switch vendors claim to support Layer 4 (the Transport Layer) and above. Load balancing switches, for example, use information beyond Layer 3 to distribute packets across large server farms. However, there's blurring of the levels in these more sophisticated products such that it's now more usual to refer to them as multi-level switches. Multi-level switches are more expensive and complicated to deploy and mostly reserved for specialist applications.

swA(config)#ip routing (to enable routing if it is disable!) swA(config-if)#no switchport (making this port as a layer3 port.sw1(config)#ip routing sw1(config)#int g1/1 sw1(config-if)#no switchport sw1(config-if)#ip add 10.10.10.10255.255.255.0 sw1(config-if)#no sh sw1(config-if)#end

If you are using cisco L3 switch . used cdp neighbors command from a cisco device connected to it directly , or simply you can ping L3 switch .. Make sure you enable ip routing command first to enable L3 features on switch .....

use ping command from any cmd.

There's something called ping....which can check anything related to L3.

Kindly give some details that what you are actually asking for? If you wanna check the routing (the L3 function) of the switch working or not so check via following command:

show ip route