On 12/18/06, Mark Belanger <mark_belanger at ltx.com> wrote: > Matthew Miller wrote: > > On Mon, Dec 18, 2006 at 04:17:59PM -0500, Mark Belanger wrote: > >> I have many different centos machines that are hanging > >> regulary. I believe this is due to something our application > >> is doing - not a centos specific problem. > >> When the machines hang, there is no access to the console > >> or remote access(ssh, rsh, etc). > > > > Do you mean that there's no *access* to the console, or that it doesn't > > *respond* on the console? > > X is frozen, no way to switch the console(i.e. Ctrl-Alt-F1, Ctrl-Alt-Backspace), > and no way to access the machine remotely. > Consider setting up a serial console so that you might be able use magic-sysreq to gather infomation on the kernel and processes. The serial console should not be effect by X freezing (i.e. you would have a seperatate terminal session setup too it, prefereably in a GUI environment not on that machine. Cheers...james P.S. The documentation on magic sysreq is in the kernel docs.