Gentoo Box Drops Off Network (Long)

[Gerald Combs]

On Thu, 1 May 2003, Steven Elling wrote:

> The network card is a Linksys LNE100TX running at 100 Mbps full-duplex and 
> dmesg shows the chipset as an ADMtek Comet rev 17.  I am using the tulip 
> driver and it is built into the kernel.  The system has an AMD Athlon Tbird 
> running at 900 MHz so I doubt the system is too slow.
> 
> The first time I ran miii-diag it showed the following:
> 
> Using the default interface 'eth0'.
> Basic registers of MII PHY #1:  3100 7869 001d 2411 05e1 41e1 0007 2001.
>  The autonegotiated capability is 01e0.
> The autonegotiated media type is 100baseTx-FD.
>  Basic mode control register 0x3100: Auto-negotiation enabled.
>  Basic mode status register 0x7869 ... 786d.
>    Link status: previously broken, but now reestablished.
>  Your link partner advertised 41e1: 100baseTx-FD 100baseTx 10baseT-FD 
> 10baseT.
>    End of basic transceiver information.
> ----------
> 
> The network card is set to auto-negotiation and mii-diag reported the link 
> as "previously broken, but now reestablished."  Do you think that because 
> the network card is set to auto-negotiation it is breaking the network 
> connection and trying to renegotiate the media type and speed thereby 
> causing the RX errors and overruns?

I don't know.  On a system here at work, mii-diag says:

rufus:/home/gerald# mii-diag eth0
Basic registers of MII PHY #1:  3000 782d 02a8 0154 05e1 cde1 0009 0000.
 The autonegotiated capability is 01e0.
The autonegotiated media type is 100baseTx-FD.
 Basic mode control register 0x3000: Auto-negotiation enabled.
 You have link beat, and everything is working OK.
 Your link partner advertised cde1: Flow-control 100baseTx-FD 100baseTx
10baseT-FD 10baseT, w/ 802.3X flow control.
   End of basic transceiver information.

Which provides an example of an unbroken autonegotiated link.  A 900 MHz
Athlon has more than enough oomph to move data from the NIC to memory at
wire speed.  The fact that you have overruns (and that it was working fine
previously) suggests an issue with the driver.