A simple network - 7 switches, 347 ports, single subnet (for now), all ports on the default VLAN. One of the seern switch has this issue after Port Discovery - On the Device Tracker Home page, in "Top 10 Nodes by Percent Used" the top switch is in yellow rather than green; and, I cannot search for an IP address of any host I know is plugged into that switch. It's a 3com 4500G. It's the backbone switch; meaning, it has plugged into it servers, other switches, routers, etc. Anyone with advice on how I figure out shat's happening? Thanks.