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Suddenly I'm no longer able to resume screens I have running on a remote machine. I've never had this happen in a few years of running this machine. I don't know that it's connected but I did run yum update last night.

I can see the screens listed and they're properly detached:

18709.bungee    (Detached)
5462.mc (Detached)
7045.ftb    (Detached)

Yet when I try to resume any of them, all I get is the cursor on the next line. Any attempt to exit or detach fails and I have no choice but to close my ssh connection entirely.

I have some services running in those screens that I need to gracefully shutdown before I try rebooting the server itself.

Is there any known cause of this? Or any way for me to get into a screen?

  • Make sure your TERM environment variable is properly set before you start screen. You can also look at the scrollback within the screen via <control-a>:copy - then vi commands will move you up and down through the scrollback. esc to exit scrollback mode. Finally, you may not realize that screen can give you multiple virtual windows. Try <control-a>n to cycle among them once you're in a screen. – Dan Pritts Sep 16 '15 at 14:51
  • TERM=xterm for me, I don't know if that's changed because I don't remember what it was beforehand. – BotskoNet Sep 16 '15 at 15:14
  • as long as it's set to something reasonable for your current terminal, it's fine (and xterm is almost certainly fine for whatever you are using). screen will deal with different terminals. Just wanted to ensure it was set to SOMETHING. – Dan Pritts Sep 16 '15 at 19:49
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Since 4.2.1 screen uses file sockets instead of named pipes for IPC by default. If you have updated screen from such old version your old sessions will become inaccessible. You have to destroy old sessions or downgrade screen to close sessions properly.

  • I'm not sure I'd call what I had "old" because I run updates very regularly, but is there a way I can check what was updated with my last yum update command, what version I had before, or what version of screen was used to create these? – BotskoNet Sep 16 '15 at 14:55
  • Sorry I'm not familiar with linux packet managers. May be there is some logfile exists where all updates are logged. – Kondybas Sep 16 '15 at 15:01
  • Just now I've have updated screen from 4.2.1 to 4.3.1 so it is very probable that you have stuck with version incompability. – Kondybas Sep 16 '15 at 15:05
  • The update yesterday brought me to Screen version 4.00.03 (FAU) 23-Oct-06 – BotskoNet Sep 16 '15 at 15:18
  • Ok, I see the update brought me from screen-4.0.3-16.el6.x86_64 -> screen-4.0.3-16.el6.x86_64, but the -16 package is no longer available, because yum downgrade screen fails and 4.0.3-18.el6 is the only version shown as an available package. – BotskoNet Sep 16 '15 at 15:58

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