[CentOS] when to reboot after updates

[Les Mikesell]

Robert Heller wrote:
> At Thu, 09 Apr 2009 07:49:30 -0400 CentOS mailing list <centos at centos.org> wrote:
> 
>> What is the rule of thumb for reboots after updates...
>>
>> Certainly if I update from 5.2 to 5.3 I reboot.
>>
>> But if you update something like krb5 or pam
>> does that require a reboot? Does the "fix" get automatically loaded and used
>> or do you just do a reboot always?
> 
> You only *really* need to reboot if/when you update the kernel. Yum/RPM
> takes care of restarting daemons, etc. during the update process.  This
> is NOT MS-Windows....

Yes, but any program that is already running will keep using the old 
versions of the program, libraries, open files, etc., retaining the disk 
space and not sharing the in-memory copy with new instances that start 
after the update.  And since modern programs like to dynamically load 
library modules as needed while running you can get a strange mix of 
old/new versions running at once.

-- 
   Les Mikesell
    lesmikesell at gmail.com