phil@shl.com (Phil Trubey) (01/31/91)
I have this annoying problem with my SCO Unix machine. Every once in a while when I'm logged in via a Telnet session, the Unix machine just drops my connection. In fact it drops all telnet connections from my machine if I have multiple connections outstanding (I use PC/TCP from a PC to telnet in). When it drops the connections, my session just freezes until PC/TCP realizes that the other end is not talking anymore and then lets the connection go. After dropping my connections, I can't initiate new connections - it just times out. A few minutes later I can initiate new connection and continue as if nothing happened. Any ideas on what might be causing this? Thanks, -- Phil Trubey SHL Systemhouse Inc. (Internet: phil@shl.com UUCP: ...!uunet!shl!phil)
fitz@wang.com (Tom Fitzgerald) (02/01/91)
phil@shl.com (Phil Trubey) writes: > I have this annoying problem with my SCO Unix machine. Every once in > a while when I'm logged in via a Telnet session, the Unix machine just > drops my connection. One problem is, apparently SCO's rlogin and telnet demons will die horribly if a "suspend" character comes across the line. As shipped, this is a null (^@) character and you can trash your session by typing a control-space on most workstations. To avoid this, "stty susp '^-'" in your .profile or /etc/profile if you're telnetted in. This sounds only vaguely like your problem though. If it doesn't apply, never mind. --- Tom Fitzgerald Wang Labs fitz@wang.com 1-508-967-5278 Lowell MA, USA ...!uunet!wang!fitz
leo@unipalm.uucp (E.J. Leoni-Smith) (02/07/91)
phil@shl.com (Phil Trubey) writes: >I have this annoying problem with my SCO Unix machine. Every once in >a while when I'm logged in via a Telnet session, the Unix machine just >drops my connection. In fact it drops all telnet connections from >my machine if I have multiple connections outstanding (I use PC/TCP from >a PC to telnet in). When it drops the connections, my session just >freezes until PC/TCP realizes that the other end is not talking anymore >and then lets the connection go. After dropping my connections, I can't >initiate new connections - it just times out. A few minutes later I can >initiate new connection and continue as if nothing happened. >Any ideas on what might be causing this? I have seen similar behaviour on another TCP/IP : My guess - and it is only a guess - is that you might be seeing two packets hitting the ethernet adapter in quick succesion, the second whilst the first is still being processed under interrupt. Then the driver exits the ISR clears down the interrupt - and maybe doesn't reset the hardware correctly. I have written bad hardware interface code like this om several occasions. You don't say what hardware you are using: I have heard rumours of this behaviour with certain intelligent cards...but no more than that. In my case it happened on a development release on a WD8003 - but so infrequently that it was not a problem. Sometimes Heavy NFS would cause it, and it would sometimes clear if i sent an outbound packet - sometimes not - needed reboot. I am intereseted in further detail. I run the support dept of a company that has to support connections TO SCO (we don't sell that) so if I can get info - it saves ME time!