Subject: Re: gem (ERI/GEM/GMAC Ethernet device driver) has problems on macppc -current
To: Timo Schoeler <email@example.com>
From: Steven M. Bellovin <firstname.lastname@example.org>
Date: 10/19/2005 08:06:55
In message <4356070F.email@example.com>, Timo Schoeler writes:
>>>>Do you use hardware checksum offload?
>>>no. it's disabled.
>> So that's not the reason. I asked because I had it enabled.
>>>(btw: IIRC i had the same issue on a G3 b&w in the office (this runs a
>>>bm0 NIC then) where i put in some spare NICs (fxp) to circumvent the
>>>problem. i'll do some reseach when i'm in the office.)
>> Is it that bad? My G4 spilled out that message every few minutes and
>> the network connection worked fine.
>uhm, i thought it to be noteworthy.
>the problem scales with the speed the packets come in/go out:
>* downloads from an ftp server outside the LAN (connected with 4Mbps)
>give no errors;
>* transfers with a host in the same LAN at 10Mbps give rarely errors of
>this kind, but they are there;
>* transfers with a host in the same LAN at 100Mbps gives a busy syslogd...
>the problem starts immediately, as i already noted, as soon as the ssh
>handshaking takes place.
That sure sounds like a collision problem. It could be the switch or
its configuration, it could be a full/half-duplex mismatch (try setting
that explicitl), or it could be something about the NIC or driver.
--Steven M. Bellovin, http://www.cs.columbia.edu/~smb