Kevin_Cain
August 7th, 2015, 05:50 PM
After restarting a working system after a series of routine updates, Ubuntu hangs at the login screen. There are a few troubling flashes before the login screen arrives -- but the login GUI draws fine. By 'freeze', I mean that both keyboard and mouse are unresponsive, I am unable to switch to a terminal via Alt-Ctrl-F1, et cetera.
While there are many forum threads detailing freezes after login and black screens before login, this does appear to be something different. The login screen simply freezes completely after it is drawn, preventing me from entering a password. A few seconds after the freeze, a notification messages pops up in the upper right of the screen to say the network is offline, and after a minute or two more, the screen goes black.
- Ubuntu 14.04.3 LTS x64
- Dual Intel Xeon E5-2640V3 (Haswell) 2.6 GHz 8-Core Processors
- Supermicro DP Xeon Motherboards - Socket R3
- 128GB server RAM
- EVGA GeForce GTX 970 Graphics Card
I've tried the following, including a full reinstall of Ubuntu:
0. Alternate keyboard/mouse. Unlikely, I know, but to rule out trivial driver troubles or hardware I swapped keyboards & mice.
1. Reboot into recovery menu, which also freezes before a selection is made, as shown below. Note the strange characters at the window border:
http://www.insightdigital.org/Ubuntu_recovery_mode_frozen.jpg
2. Catching boot messages, by taking a photo of the screen I caught a persistent, fleeting 'failed to start Load Kernal Modules...' message.
3. Assuming the problem stems from GPU drivers, next from the grub text edit 'e' option I tried removing 'nomodeset' in the kernal boot options (as per http://ubuntuforums.org/showthread.php?t=1613132), with no effect. Each reboot the system freezes at login as above.
4. Compare with boot via Ubuntu 14.04 live USB -- this I can do without a problem.
5. Full system reinstall atop my existing root and swap volumes (with the reformat and download updates options both ticked). On reboot the system freezes at login, the same behavior as above.
While there are many forum threads detailing freezes after login and black screens before login, this does appear to be something different. The login screen simply freezes completely after it is drawn, preventing me from entering a password. A few seconds after the freeze, a notification messages pops up in the upper right of the screen to say the network is offline, and after a minute or two more, the screen goes black.
- Ubuntu 14.04.3 LTS x64
- Dual Intel Xeon E5-2640V3 (Haswell) 2.6 GHz 8-Core Processors
- Supermicro DP Xeon Motherboards - Socket R3
- 128GB server RAM
- EVGA GeForce GTX 970 Graphics Card
I've tried the following, including a full reinstall of Ubuntu:
0. Alternate keyboard/mouse. Unlikely, I know, but to rule out trivial driver troubles or hardware I swapped keyboards & mice.
1. Reboot into recovery menu, which also freezes before a selection is made, as shown below. Note the strange characters at the window border:
http://www.insightdigital.org/Ubuntu_recovery_mode_frozen.jpg
2. Catching boot messages, by taking a photo of the screen I caught a persistent, fleeting 'failed to start Load Kernal Modules...' message.
3. Assuming the problem stems from GPU drivers, next from the grub text edit 'e' option I tried removing 'nomodeset' in the kernal boot options (as per http://ubuntuforums.org/showthread.php?t=1613132), with no effect. Each reboot the system freezes at login as above.
4. Compare with boot via Ubuntu 14.04 live USB -- this I can do without a problem.
5. Full system reinstall atop my existing root and swap volumes (with the reformat and download updates options both ticked). On reboot the system freezes at login, the same behavior as above.