Hello, re bypass mechanisms on on other platforms they can be just purely passive relays, that when power is attached to the system and the bios /EFI firmware confirms load (after the beep) an 8pole relay (that is normally closed electrically linking two RJ45 ports together, it can be useful in scenarios if you have only 1 interface from an uplink provider and only have routers with a single power supply each and you want to create a failsafe failover... I tend to use a scenario where the OS replicates the connectivity when the OS loads, i.e. place the 2 interfaces that are in the same bypass group into a bridge...
one has to be careful not to create loops with that type of config... as far as im aware there is usually dip switches or jumper pins on the mainboard to facilitate it... sorry for going off on a tangent here.. but when I heard bypass I thought I would share some of my humble experience here... All the Best Tom On Tue, 20 Oct 2020 at 13:39, Stuart Henderson <s...@spacehopper.org> wrote: > On 2020-10-20, Harald Dunkel <harald.dun...@aixigo.com> wrote: > > On 10/19/20 9:46 PM, Stuart Henderson wrote: > >> On 2020-10-19, Harald Dunkel <ha...@afaics.de> wrote: > >>> > >>> What would these bypass problems look like? Hopefully the bypass > feature > >>> can be turned off/ignored. > >> > >> If there are problems then possibly 2 of the ports either won't work > >> or will be connected directly to 2 of the other ports until a magic > >> command is sent somehow (either gpio or via some memory mapped io > >> port I guess, I don't know the hardware). > >> > > > > You mean the bypass might be active, even though its not configured and > > power is on? That sounds like a fatal problem to me. Is this restricted > > to OpenBSD or are other operating systems affected as well? > > I don't know how it works on this hardware. The general idea of bypass > NICs is so that they connect ports straight-through if the OS is not > running correctly, so it depends how they detect whether the OS is running > as to whether that will work. > > One would hope that it can be disabled if necessary, but one would also > hope that BIOS/firmware vendors don't make silly mistakes and experience > has shown that this is not always the case ;) > > It will probably be OK. But with new hardware, who knows! > > -- Kindest regards, Tom Smyth.
