Fred Smith
2013-Oct-11 01:08 UTC
[CentOS] suddenly X gives black screen with small clock cursor
On Thu, Oct 10, 2013 at 08:08:08PM -0400, Fred Smith wrote:> Gang: > > I'm puzzled... > > I rebooted a while ago (and in between the down and up, I installed Fedora > 20 Beta on a USB hard drive, making sure it wouldn't mess with my Centos > system). The install went fine, but afterwards, when I reboot Centos, it > comes up with a black screen and a clock as the mouse cursor (small clock). > > Tried CTRL-ALT-BKSP and the clock disappears and reappears. > > I did "init 3" to stop the apparently busted X server, removed the X lock > file from /tmp and attempted "startx", which didn't work either. > when startx is run I get a bunch of messages ending with: > > Initializing built-in extension XFree86-VidModeExtension > Initializing built-in extension XFree86-DGA > Initializing built-in extension XFree86-DRI > Initializing built-in extension DRI2 > Loading extension GLX > Loading extension NV-GLX > Loading extension NV-CONTROL > Loading extension XINERAMA > xinit: Permission denied (errno 13): cannot open /dev/null: Permission denied > > waiting for X server to shut down Server terminated successfully (0). Closing log file. > > curiously, when I log in on a console I also get this: > > -bash: /dev/null: Permission denied > -bash: /dev/null: Permission denied > -bash: /dev/null: Permission denied > -bash: /dev/null: Permission denied > -bash: /dev/null: Permission denied > -bash: /dev/null: Permission denied > > So something is seriously hosed here. Can anyone give me a clue? > > thanks!So, I don't know what the heck happened, but I have what looks like a solution: a number of important files in /dev somehow had their permissions changed. I had to do the following: chmod a+rw /dev/null chmod a+rw /dev/urandom chmod a+rw /dev/zero chmod a+rw /dev/full chmod a+rw /dev/random After which X started and the complaints about /dev/null went away. As I worked thru fixing first /dev/null, each step got me a bit further, with more complaints about inaccessable /dev/ entries, so I just kept fixing them until the complaints went away. I also compared permissions in /dev against my Fedora 19 netbook, which is how I knew what permissions to use for the rest, as well as being where I found correct permissions, as well as /dev/zero and /dev/full being wrong. I have NO CLUE what hosed the permissions, and I can't be sure that there may not be some other items also wrong (that I can't see because they don't appear on the F19 system). Can anyone suggest an accurate way to have the system fix all the permissions in /dev? some arcane options on rpm, perhaps? thanks! Fred> > -- > ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- > God made him who had no sin > to be sin for us, so that in him > we might become the righteousness of God." > --------------------------- Corinthians 5:21 ----------------------------------- ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- The Lord detests the way of the wicked but he loves those who pursue righteousness. ----------------------------- Proverbs 15:9 (niv) -----------------------------
Fred Smith
2013-Oct-11 01:53 UTC
[CentOS] [NOT SOLVED] suddenly X gives black screen with small clock cursor
On Thu, Oct 10, 2013 at 09:08:06PM -0400, Fred Smith wrote:> On Thu, Oct 10, 2013 at 08:08:08PM -0400, Fred Smith wrote: > > Gang: > > > > I'm puzzled... > > > > I rebooted a while ago (and in between the down and up, I installed Fedora > > 20 Beta on a USB hard drive, making sure it wouldn't mess with my Centos > > system). The install went fine, but afterwards, when I reboot Centos, it > > comes up with a black screen and a clock as the mouse cursor (small clock). > > > > Tried CTRL-ALT-BKSP and the clock disappears and reappears. > > > > I did "init 3" to stop the apparently busted X server, removed the X lock > > file from /tmp and attempted "startx", which didn't work either. > > when startx is run I get a bunch of messages ending with: > > > > Initializing built-in extension XFree86-VidModeExtension > > Initializing built-in extension XFree86-DGA > > Initializing built-in extension XFree86-DRI > > Initializing built-in extension DRI2 > > Loading extension GLX > > Loading extension NV-GLX > > Loading extension NV-CONTROL > > Loading extension XINERAMA > > xinit: Permission denied (errno 13): cannot open /dev/null: Permission denied > > > > waiting for X server to shut down Server terminated successfully (0). Closing log file. > > > > curiously, when I log in on a console I also get this: > > > > -bash: /dev/null: Permission denied > > -bash: /dev/null: Permission denied > > -bash: /dev/null: Permission denied > > -bash: /dev/null: Permission denied > > -bash: /dev/null: Permission denied > > -bash: /dev/null: Permission denied > > > > So something is seriously hosed here. Can anyone give me a clue? > > > > thanks! > > So, I don't know what the heck happened, but I have what looks like a > solution: a number of important files in /dev somehow had their permissions > changed. I had to do the following: > > chmod a+rw /dev/null > chmod a+rw /dev/urandom > chmod a+rw /dev/zero > chmod a+rw /dev/full > chmod a+rw /dev/random > > After which X started and the complaints about /dev/null went away. > As I worked thru fixing first /dev/null, each step got me a bit further, > with more complaints about inaccessable /dev/ entries, so I just kept > fixing them until the complaints went away. > > I also compared permissions in /dev against my Fedora 19 netbook, which is > how I knew what permissions to use for the rest, as well as being where I > found correct permissions, as well as /dev/zero and /dev/full being wrong. > > I have NO CLUE what hosed the permissions, and I can't be sure that there > may not be some other items also wrong (that I can't see because they > don't appear on the F19 system). > > Can anyone suggest an accurate way to have the system fix all the permissions > in /dev? some arcane options on rpm, perhaps? > > thanks!Ah, it was too good to be true. Reboot returns those files to the incorrect permissions. Suggestions on where to look will be welcomed.> > Fred > > > > -- > > ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- > > God made him who had no sin > > to be sin for us, so that in him > > we might become the righteousness of God." > > --------------------------- Corinthians 5:21 --------------------------------- > > -- > ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- > The Lord detests the way of the wicked > but he loves those who pursue righteousness. > ----------------------------- Proverbs 15:9 (niv) ----------------------------- > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos-- ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- The Lord detests the way of the wicked but he loves those who pursue righteousness. ----------------------------- Proverbs 15:9 (niv) -----------------------------
John Doe
2013-Oct-11 09:50 UTC
[CentOS] suddenly X gives black screen with small clock cursor
From: Fred Smith <fredex at fcshome.stoneham.ma.us>> I rebooted a while ago (and in between the down and up, I installed Fedora > 20 Beta on a USB hard drive, making sure it wouldn't mess with my > Centos system). The install went fine, but afterwards, when I reboot Centos, it > comes up with a black screen and a clock as the mouse cursor (small clock). > > ??? chmod a+rw /dev/null > ??? chmod a+rw /dev/urandom > ??? chmod a+rw /dev/zero > ??? chmod a+rw /dev/full > ??? chmod a+rw /dev/random > > Can anyone suggest an accurate way to have the system fix all the permissions > in /dev? some arcane options on rpm, perhaps?Nothing at all in the logs...? Global check: rpm -qVa Maybe check udev confs...? JD