mah@nestroy.wu-wien.ac.at (Michael Haberler) (03/06/91)
I ran into a strange problem today. I bought a NE-1000 clone (I guess the manufacturer's name is 'GTC'). I use Rev.8 of the CU packet driver for the NE1000, on top of which I run NOS KA9Q, version 910201. Doing a ping, the IP adress is resolved properly with ARP intothe destination ethernet adress. The Echo request message gets sent, but the Echo reply gets dropped, with a icmpInError in KA9Q. Now the ka9q source indicates this error counter is incremented with either a ICMP message coming via a link-level broadcast, or a wrong header checksum. The packet trace looks fine. However, it looks like the NE1000 packet driver (or my card?) returns the wrong length on a packet receive (which would explain the failed checksum test). At least a preliminary comparison of packet traces with a 3c501 pd lead me to believe that the NE1000 pd returns wrong length fields on receive (I *think* it's 2 bytes too long on the Echo reply receive, I'll have to check that again.) The NS8390 is Rev. C. I also tried version 6 of the NE1000 driver - same effect. Any hints on what might be causing this? - michael ps.: I'm not sure on what to do with the DMA channel jumpers on the NE10000 board, but either way - no effect. -- Michael Haberler mah@nestroy.wu-wien.ac.at, mah@awiwuw11.bitnet University of Economics and Business Administration Augasse 2-6, A-1090 Vienna, Austria Tel: +43 (222) 313-36 x4796 (9-18 CET) Fax 347-555
romkey@ASYLUM.SF.CA.US (John Romkey) (03/07/91)
Returning a length that's too long shouldn't hurt things with a good IP implementation (which KA9Q is). IP carries its own length field in its header; the IP layer tends to make sure that there are at least enough bytes and then go ahead and process the packet using the IP length instead of the hardware length. This is necessary in part because ethernet has a minimum of 60 bytes, which is longer than many IP packets would be. - john romkey Epilogue Technology USENET/UUCP/Internet: romkey@asylum.sf.ca.us FAX: 415 594-1141