Hi all,

This problems spans various NIC's, Linux flavours and hardware...
Using 1000BaseSX and 100BaseFX optical networks, using either Intel or Allied Telesyn NIC's and various RedHat's and Debian on i686's.

When an Optical Fibre (SC type - multi mode) connector is removed from the NIC and not plugged back into the NIC for anytime more than about 5 seconds, the network connectivity is lost. The symptoms are that the *blinky light* never comes back. ifup/ifdown/ifconfig has no effect, packets are still attempted to be sent but the connection/NIC are dead. It requires a power cycle to restart the NIC/connection...

This is happening on all the hardware I've tested; Allied Telesyn and Intel NIC's, also on 100 and 1000Base setups. The two types of switches involved are Cisco (3550) and some Dell-based switch. It is consistent between Debian, RedHat9 and RedHat Enterprise. I've accessed Allied Telesyn specific drivers for the 100BaseFX card on one (AT-2700FX).
The router is currently manually set to 100 Full-Duplex as well as the NIC's by default and via mii-tool.

Our network switches/NIC's have no trouble picking up the connection again under various WinTel setups. XP with an Allied Telesyn NIC in particular has been tested and pops back up with no intervention...

I know that switches sometimes can be set to stop transmitting to avoid eye-damage from the IR frequencies of transmission... Is this the case in the NIC's too? Perhaps the Linux drivers are not restarting the card after seeing daylight?

Any help would be greatly appreciated...
Thanks,
Dion.