Black Screen Plague

[Guest.Visitor]

Yesterday of the 130 pc users attached to the AS400 via tcp/ip using Client Access and Client Access Express 30 of them got black screens while they were connected to the 400. On the AS400 they show as ACTIVE but they cannot get back in. Last night I had an IPL done on the 400 and today no black screens. In about ten days it will start happening again. IBM had me apply some ptf's about 3 weeks ago but now it is back. Has anyone else experienced this and if so were you able to eliminate it?????? Blue screens/black screens they are all the same to me. Desparate in Kentucky

[J.Wells]

Just a wild guess - is it possible that there are no available (varied off due to invalid signons) QPADEVxxxxx's? Joe

[Guest.Visitor]

Good shot but i disable user id for invalid signons and i do not use QPADEV. Thanks for the quick response though.

[Guest.Visitor]

Is the connection made thru a network or directly?

[Guest.Visitor]

I have no clue what caused you to get the black screen, but the reason you could not get the users back on is because the TCP session does not realize that it was disconnected and leaves the session active. If this were to happen on a twinax device or an SAA session the status would go to DSC. To get the users back on you have to either IPL, end the subsystem and restart it (QINTER), or do an ENDJOB (option 4) on all of the users. J

[Guest.Visitor]

Can the users go to the menu bar under communication and click to re-connect again?

[cwscholbe@dstsystems.com]

Would doing a CHGTCPA and changing the TCP keep alive to 1 help? The 1 = one minute. This might let TCP/IP know much sooner that the devices are no longer communicating and let them reconnect.

[Guest.Visitor]

Joe, Have you ever tried this? I have found that the device will simply be varied back on when it is next in line. You don't have to be a crack hacker, even a hack cracker might eventually guess a password, especially if you used something easy like your dog's name. It is safer to disable the profile. David Morris

[Guest.Visitor]

Yes, we have encountered this before, although this happens rarely (not every 10 days or so). We noticed that all the PCs were connected to only one ethernet cable. We traced the problem to a defective router. Problem was fixed after we replaced the router.

[Guest.Visitor]

No, it shows DISCONNECT and even if they disconnect and then try to connect again it still doesn't because the 400 still shows them as ACTIVE.