[vortex] 3c905c

[Toby Bluhm]

Originally I sent this to seawolf-list@redhat.com, but perhaps this is
the better list for my problem . . . . .

Thanks 



Okay, I'm back with more info about my problems with 3c905c & netgear
ds-516 dual speed hub connecting at 100Mb. All link lights indicate
100Mb.
ping -f runs are through the hubs to a Cabletron Smartswitch to a Tru64
Alpha running at 100Mb full.

I think it's a bug in linux. These hubs are being propagated throughout
the building & I certainly don't want win boxes to outshine the Linux
boxes:(

1.) I ran mii-diag several times in a row, each time the results cycling
through three different statuses. Looks like the card can't settle down
on link status. ping -f for 5 sec. results in up to 90% packet loss.

2.) When connected to single speed 100Mb hub, ping -f shows solid
performance, no packets dropped. Several runs of mii-diag show the same
result.

3.) Tested another PC with another 3c905c & RH7.0 to the netgear. Almost
the same problem. mii-diag results however, cycle through the different
statuses much less frequently. ping -f gets up to 50% packet loss.

4.) Installed win2k on the machine. ping -f from the other machine shows
solid performance at 100Mb, no packets dropped

5.) Tested yet another win2k box with 3c905c & ds516, performance is
solid, no packets dropped.


Three different 3c905c cards & PCs to the ds516 exhibit seemingly
consistent results.


mii-diag from 1:
----------------
[root@krakow /root]# ./mii-diag
Using the default interface 'eth0'.
Basic registers of MII PHY #24:  2000 7809 0040 6177 05e1 40a1 0000
0000.
 The autonegotiated capability is 00a0.
The autonegotiated media type is 100baseTx.
 Basic mode control register 0x2000: Auto-negotiation disabled, with
 Speed fixed at 100 mbps, half-duplex.
 Basic mode status register 0x7809 ... 780d.
   Link status: previously broken, but now reestablished.
 Your link partner advertised 40a1: 100baseTx 10baseT.
   End of basic transceiver informaion.
 
[root@krakow /root]# ./mii-diag
Using the default interface 'eth0'.
Basic registers of MII PHY #24:  2000 780d 0040 6177 05e1 40a1 0000
0000.
 The autonegotiated capability is 00a0.
The autonegotiated media type is 100baseTx.
 Basic mode control register 0x2000: Auto-negotiation disabled, with
 Speed fixed at 100 mbps, half-duplex.
 You have link beat, and everything is working OK.
 Your link partner advertised 40a1: 100baseTx 10baseT.
   End of basic transceiver informaion.

[root@krakow /root]# ./mii-diag
Using the default interface 'eth0'.
Basic registers of MII PHY #24:  2000 7809 0040 6177 05e1 40a1 0000
0000.
 The autonegotiated capability is 00a0.
The autonegotiated media type is 100baseTx.
 Basic mode control register 0x2000: Auto-negotiation disabled, with
 Speed fixed at 100 mbps, half-duplex.
 Basic mode status register 0x7809 ... 7809.
   Link status: not established.
 Your link partner advertised 40a1: 100baseTx 10baseT.
   End of basic transceiver informaion.


mii-diag from 2:
----------------
[root@spasm /root]# ./mii-diag
Using the default interface 'eth0'.
Basic registers of MII PHY #24:  2000 780d 0040 6177 05e1 40a1 0000
0000.
 The autonegotiated capability is 00a0.
The autonegotiated media type is 100baseTx.
 Basic mode control register 0x2000: Auto-negotiation disabled, with
 Speed fixed at 100 mbps, half-duplex.
 You have link beat, and everything is working OK.
 Your link partner advertised 40a1: 100baseTx 10baseT.
   End of basic transceiver informaion.


My original post:

> I'm having a problem with this combo of hardware:
> 
> Netgear DS516 dual speed hub
> 3c905c-tx 
> 
> I get terrible network performance when the units try to talk at 100Mb.
> 
> If I force the card to 100Mb half >not< happy.
> 
> If I force the card to 10Mb half it will be happy.
> 
> If I plug it into a
> plain single speed 100Mb or 10Mb hub, it will be happy.
> 
> If I plug it into a switch, it will be happy.
> 
-- 
toby

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