On Tue, May 29, 2007 at 02:18:36PM -0700, Garrett D'Amore wrote:
> One problem I have is that assumption that Link speed and duplex are 
> meaningful all the time works.  For non-802.3 links, they aren't.  Even 
> the speed is not necessarily meaningful.  (With 802.11 the speed can 
> change dynamically, very frequently.  You don't want to log that for 
> certain!)

Indeed.  The log message in question may have to vary by media type.
For 802.11 link up/down may not be so interesting either, rather, link
speed ==/!= 0 would be.

> For other devices, the fact that an external or internal transceiver is 
> likely to be just as relevant as speed and duplex setting.  (NICs that 
> have an external transceiver, for example.)  Or media, for nics that 
> have both copper and fiber ports.)

Why?  The transceiver is a physical attribute of the NIC -- if you need
one and it's removed then you'll not have link.

> Again, trying to come up with something _in the logs_ that can be 
> consistent across all drivers, in a way that doesn't worsen breakage, 
> seems challenging.

The log message in question should be consistent across all drivers for
the same media type.

> The one thing that seems to be universal is the link up/down state.  

Not so.  For wireless link state and speed both depend on signal
strength.

> Which is probably why that is what is what is record in the MAC layer 
> rather than the device driver kstats.

I don't get this.

> Anyway, if folks are dead convinced that we have to have link speed and 
> duplex for 802.3, I have figured out how to add it without too much 
> engineering effort or risk.  Should we also be logging e.g. the SSID for 
> 802.11 links?

Can it change without sysadmin intervention?  No.  Or did you mean the
base station's ID?  If so, then, maybe!  (It'd be nice to see roaming
reflected in the logs, no?)

> >>Hope that answers this concern.
> >>    
> >
> >It doesn't.
> >  
> 
> It doesn't?  Why not?  Or are you saying it doesn't address the 
> aforementioned "other cases" that people gave?

I was.

Reply via email to