In an industrial plant we're designed and delivered the L1 and L2 networks (in this case L1 and L2 accordingly to ISA 95 stack not networl ISO stack!).
We've used Netgear GS724 switches monitoring their service level with Paessler Ipcheck (http://www.paessler.com/ipcheck) which uses IGMP to poll them every minute.
Randomly and very often the switches use to crash but They still provided connectivity to the linked devices, you could ping them but not the switch itself.
After spending a lot of time trying and changing a lot of configurations, we received a new release of the firmware (an alpha version) from Netgear so don't waste time checking configurations!