Greetings linux net gurus -- I can't connect my laptop and desktop via a funny coax ethernet, using a medfiaq convertor and a PCMCIA card, and I hope somebody solved parts of similar problems before and can help. I want to connect my two home PCs, a Dell Dimension XPS desktop with 3c590-COMBO "Vortex", and a Dell Inspiron 7000 with 3c575 "Cyclone" Fast Ethernet XL card. I have a problem which is either hardware or software, and I see many symptoms which are interesting. I'd appreciate any hints on what so examine/try next, and apologize if this question was covered previously on the list -- any pointers to any solutions are welcome. Since my Vortex is a combo, having coax BNC, and I also happened to have a media convertor BNC-RJ45 with (a) 10BaseT link pulse sensor (switchable) (b) RX & Collision indicators at the both ends, I decided that coax ethernet is what I want -- since I'll also put my future computers on it, and I have ethernet capable Macs already. I run RedHat 5.2 on the Dimension, and same thing on the Inspiron. Both installations were made out of the box. However, I recompiled the kernels on both machines, and I also upgraded the Inspiron's kernel to 2.2.5 in order to take the full advantage of the latest PCMCIA tools, 3.0.9. So 3c575 works fine except it dies in its sleep -- doesn't come back after resume, but taking it out/reinserting puts the link back online. I'll follow up with the PCMCIA guys on that. The hardware looks as follows: the media convertor sits on my desk so I can observe all the indicators. Convertor's link sense on RJ45 end is on (since the link sense switch is on and 3c575 responds with pulses as a new RJ45 ethernet device should). 3c575 LED for 10 Mbps is on, and 100Mbps is properly off (my convertor is 10Mbps, and so is Vortex). The software configuration is as follows: the Dimension is called yaw, and the Inspiron is called roll. The /etc/hosts file on both machines looks as follows: -----/etc/hosts 192.168.0.1 yaw yaw.suffix.com 192.168.0.2 roll roll.suffix.com -----. I configure the eth0 interface on yaw as follows: $ ifconfig eth0 192.168.0.1 netmask 255.255.255.0 up $ route add -net 192.168.0.0 eth0 Similarly, I configure roll as follows: $ ifconfig eth0 192.168.0.2 netmask 255.255.255.0 up $ route add -net 192.168.0.0 eth0 Each machine can now successively ping itself as localhost or by name (yaw, roll). However, when I try to ping another machine, ping waits showing nothing, and ^C reports all packets transmitted and lost. ifconfig on both machines reveals that TX is 0, and the lost packages show only in the "carrier" field, not documented in my Olaf Kirsh's book (1995). However, a strange quirk can be observed with netstat -i: all the packages lost on eth0 trying to ping another machine, and showing only in the "carrier" field on ifconfig eth0, are showing as successfully RX and TX for lo, the loopback! So they never reach the eth0 but somehow go to loopback statistics? Saying arp -a on both machines shows empty tables, nothing there. And most disturbingly but promising, the following hardware effects can be observed when trying to ping another machine: When pinging yaw from roll, both ends of the convertor blink RX AND Collision synchronosuly with the packets to be sent. No RX/TX success is reported though by ifconfig, only "carrier" (and strangely on lo's successful RX/TX). When pinging roll from yaw, no blinking on the coax end is observed otehr than periodic probably "sensing" blinks. The coax end of the convertor blinks every so often, dozens of seconds or so, even when teh RJ45 end is disconnected. Now, I am at a loss as to where to look next. Any comments? Cheers and regards, Alexy Khrabrov University of Pennsylvania Philadelphia, PA - To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to [EMAIL PROTECTED]
