On 06/02/2013 18:34, m.roth at 5-cent.us wrote: > Les Mikesell wrote: >> On Wed, Feb 6, 2013 at 11:19 AM, SilverTip257 <silvertip257 at gmail.com> >> wrote: >>> If one of your hosts intermittently loses connectivity, the switch will >>> broadcast that traffic to all ports because it can't find the host's MAC >>> address. >>> >>> (And what Les said about the switch broadcasting traffic until it learns >>> MAC addresses.) >> Some spanning tree events will force the switch to re-learn MACs too. > I should have mentioned this switch is *only* in use on our subnet, though > of course we go through it to go Out There, there are gov't firewalls > outside of it. All the traffic is only on our subnet, in this case, and > the weirdness was intermittent. > > At the time, there were two heavy users (me, doing an offline backup, from > one room to another, the latter with the server being hit by me in it, and > at that switch, and another user doing heave scientific computing). That > is, of course, in addition to all the other normal traffic from dozens of > other servers. > > Btw, he's not seeing it today, but I'm not running any more backups just > now.... > > You may have some trunking issues if you use VLANs, inter-operate these switches with non-Cisco equipment and have left every port on the switch in the default VLAN1. Have you actually configured the switch, or did you just plug it in and get running? -- Regards, Giles Coochey, CCNA, CCNAS NetSecSpec Ltd +44 (0) 7983 877438 http://www.coochey.net http://www.netsecspec.co.uk giles at coochey.net