[BBLISA] How do you detect bad hardware on your network?

[Alex Aminoff]

We have an office network with about 200 desks, with Dell managed 24 and 
48 port switches, with spanning tree and broadcast storm control. At the 
desks and carrels, we have many small 4 and 8 port non-managed switches. 
Sometimes one of these small switches malfunctions in a way that affects 
large portions of our network, but intermittently. What are best 
practices for detecting and pinpointing this sort of problem?

Thanks,
  - Alex Aminoff
    NBER