[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference turris::digital_unix

Title:DIGITAL UNIX(FORMERLY KNOWN AS DEC OSF/1)
Notice:Welcome to the Digital UNIX Conference
Moderator:SMURF::DENHAM
Created:Thu Mar 16 1995
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:10068
Total number of notes:35879

9121.0. "Can vmunix be replaced ?" by ZPOVC::YINGYONG () Tue Mar 11 1997 21:44

    To make a new kernel that has been built effective, one has to replace
    the /vmunix with the new kernel and then reboot the system.
    
    Can I replace /vmunix and reboot the system at later date because it is
    a production system ?  Will there be discrepancy because the kernel
    that is loaded has been replaced ?
    
    Rgds.
T.RTitleUserPersonal
Name
DateLines
9121.1VAXCPU::michaudJeff Michaud - ObjectBrokerTue Mar 11 1997 23:1314
> Can I replace /vmunix and reboot the system at later date because it is
> a production system ?

	yes

> Will there be discrepancy because the kernel
> that is loaded has been replaced ?

	yes.  anything that reads /dev/mem or /dev/kmem and gets
	the addresses to read out of the symbol table in /vmunix
	will usually read the wrong memory and hence the output
	or whatever will be screwed up.

	why not replace /vmunix only when you are ready to reboot?
9121.2Thank you for the prompt replyZPOVC::YINGYONGWed Mar 12 1997 00:181
    
9121.3SMURF::DENHAMDigital UNIX KernelWed Mar 12 1997 20:514
    More importantly (to me anyway) is that if your system crashes
    and the /vmunix isn't the one that was booted, the crash
    dump will be useless unless that original vmunix can be reproduced.
    It will certainly cause confusion for a while....