jand@maestro.htsa.aha.nl (Jan Derriks) (05/31/89)
A few months ago I posted the following article:
- ...Sometimes, when a terminal is switched on the /dev/ttyxx line
- 'hangs'. Nothing else but a reboot of the system helps.
- An echo >/dev/ttyxx appears on the screen, but I cannot
- read /dev/ttyxx at all...
In article <52535@uunet.UU.NET> rick@uunet.UU.NET (Rick Adams) wrote:
- >..Currently, we have a very serious problem with terminal ports hanging.
- >This hang means that the Sequent totally ignores data sent from the
- >terminal. Nothing short of rebooting will clear this hang. ...
- > ... We have to reboot the system on a daily basis to free stuck ports.
We have found two workarounds to prevent this problem:
1. Never switch off your terminal (adhesive tape across the switch).
2. Don't use the rs232 DTR-DCD signal (connect 8 dtr to 20 dcd at the
connector on the sequent side).
The disadvantage of 2. is that users will not be logged out when they
turn off their terminal or hang up the modem line.
Still, *if* a tty line hangs only a reboot will help...
Jan Derriks AHA-TMF (H.T.S. 'Amsterdam')
jand@htsa.aha.nl (..hp4nl!htsa!jand) Europaboulevard 23
phone: +31 20423827 1079 PC Amsterdam, The Netherlandscsg@pyramid.pyramid.com (Carl S. Gutekunst) (06/01/89)
>2. Don't use the rs232 DTR-DCD signal (connect 8 dtr to 20 dcd at the > connector on the sequent side). > >The disadvantage of 2. is that users will not be logged out when they >turn off their terminal or hang up the modem line. This is a serious security hole. User hangs up leaving an active session, and the next person who dials in gets the same session. If they're a nice company employee, they'll log out and log in to their own account. If they're trying to crack the machine, they've just succeeded. I'd rather deal with the tty hangs. You can't break into a hung line. ;-) But, why hasn't Sequent put its hands around Systech's throat and *demanded* they fix this problem? <csg>