Re: Checking the speed of my Ethernet interface


michael.mcgarry@xxxxxxxxx wrote:
Cool, that worked.

The problem I have is that my card is Gigabit ethernet and I am
connected to a Gigabit Ethernet switch port. However, mii-tool reports
100Mbps negotiated. How can I fix this?

OK, mii-tool works. Did you try ethtool? It has a more complete
interface to the nic than mii-tool _if_ your driver supports ethtool.
It might provide more clues. Use the man pages for both.

Essentially, there is nothing you can do to _force_ the nic and switch
port to use 1000Mbs. They must auto-negotiate the speed and agree that
the link can support the rate. If there is a problem when they
negotiate, they will fall back to 100Mbs.

About all you can do is double check the configuration of the switch
port and the nic to make sure that some setting is not preventing the
GigE link and double check/replace the cable between them. The cable
is cat5e or cat6 isn't it? If it's an older cat5 cable it likely won't
support the GigE link speed. You might try to run a short cat5e or
cat6 patch cord between the switch port and nic if you can get them
close enough together to confirm that the cable is the the problem.

After that, you're down to chasing ghosts :-)

Every GigE link has it's own peculiarities and chasing down the fault
can be tedious and frustrating. You just have to be determined and go
one step at a time ferreting out the cause.

good luck,
prg

.