Too much traffic to a mostly-unconnected switch

I've a small switch (3512-XL) which is currently connected to nothing but another switch. The connection is an ISL trunk.

I'm seeing a non-trivial amount of inbound traffic to the switch (~65Kb or so; it varies). There's no oubound traffic. What sort of thing would cause that inbound traffic? The one thing of which I can think is broadcast traffic on VLANs for which the switch is configured, but that's far too much traffic for just broadcasts.

Another thing I tried was to explicitly shutdown all ports (but the trunk to the other switch). No change.

For what other sorts of things should I be looking?

Thanks...

Andrew

Reply to
Andrew Gideon
Loading thread data ...

Over what span of time does the 65k come in? ... it does seem trivial. .... however, what comes in also depends on what you are running on your network. To answer your own question, you should install a PC on that small switch, and then run Ethereal or any other packet capture utility. This will be the best way for you to learn a lot quickly. Spanning Tree, OSPF, HSRP, NetBIOS, DNS, ARP, Multicasts, appletalk, vines, decnet, dhcp, bootp, ... . Hope this helps

Reply to
dmcollin

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.