Giles Coochey wrote: > On 09/07/2011 01:06, Les Mikesell wrote: > >Turning off negotiation pretty much guarantees problems if > >anything changes at the other end or you use an unmanaged switch. > >And the gigabit spec requires auto-negotiation. > > Let me make it clear - auto-negotiation only works if > auto-negotiation is configured on both sides. It does not work if > one side hard codes the speed and duplex. Both sides have to be set > for it to negotiate. Agreeing on speed and duplex ensures that it > will work. > > If something is going to change on the remote end without you > knowing, or your provider is using an unmanaged switch then it's > time to change provider :-) - they obviously are cheapskates and > don't have any change management control on their systems. > > Gigabit is different.
My reading of the spec is that when a port is configured for 1GbE over 1000BASE-T (copper), "disabling" auto-negotiation disables the advertising of the auto-negotiation for 10BASE-T and 100BASE-T, but auto-negotiation is still advertised and operational for 1GbE. Auto-negotiation cannot be disabled for 1000BASE-X (optical fiber). Deviation from the spec would mean such kit is Ethernet-like. An ability to "set" auto-negotiation one way in the user interface while leaving the hardware in a different - standards conforming - state is possible. -- Charles Polisher _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
