It sounds like the Netgear Layer 2 802.3 flow control is buggy. It sounds like you can't turn it off, though, because it's not a managed switch. Should have bought Cisco!? :-)
You can turn it off on the workstations, though, and I would somewhat hesitantly recomment that. You might risk other problems by disabling it. Flow control should be negotiated with autonegotiation, but we know how well that works for duplex mode. Nontheless, if it were me, I think I would turn it off on the workstations carefully, as a test to start with. I'd be interested in other people's opinions, but I think flow control at the data-link-layer is risky and unnecessary anyway. No offence to Netgear (really!) but I'm not sure I would trust them to do it right, especially on a low-end switch. So, let's say a switch port has been flow controlled and told not to send any packets for a while. What does it do with the packets? How much buffering can it support? Does it have features to avoid head-of-the-line blocking? Will the flow control on that interface cause problems for other interfaces? TCP already does end-to-end flow control. Of course, not every application uses TCP, but a lot do. I think that's a better way to handle it. And one final comment, if you really need to be flow controlling traffic, perhaps you should just upgrade the bandwidth? Ethernet flow control sounds like a bandaid over a design problem to me.... What do others think? Do you use 802.3x flow control? Thanks. Priscilla [EMAIL PROTECTED] wrote: > > I need some expert option on the following matter: > > I have a Netgear Fast Ethernet Switch FS608 (which does 802.3x > Flow > control) connected to a DLink 5 port switch (no flow control) > > Twice this week, the FS608 locked itself causing ALL traffic in > the company > to be disrupted. The problem was solved by power cycling the > switch. > > All the clients on the FS608 have 3Com network cards that > support flow > control. > > Here are my questions: > > 1) Are there some caviat in running 802.3x I am not aware of? > I did > extensive research before implementing this and did not find > any issues with > the implementation of the technology? > > 2) Is there an issue of running 802.3x on one switch and not on > the other? > > 3) I could turn off the 802.3x feature on all the workstations > but I can't > turn it off on the FS608. This is NOT a managed switch. Any > suggestion on > how to troubleshoot this problem? > > Thank you, > > Pierre-Alex > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=74516&t=74455 -------------------------------------------------- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
