CentOS - May 2012 - when is the o.s. considered to be at a certain minor version? Or, is it safe to apply only certain package updates from the next release version?

Two related questions about the minor release numbers (e.g. the 'x' in
5.x or 6.x) :

1) What constitutes the o.s. being at a particluar minor release?  Typically,
when you install you are getting a package set available from a specific minor
release number.  But what minor release is the o.s. at if I just update the
centos-release package, and no other package?  Typically, a 'yum update'
is said to take your whole package set to the latest minor release.  But what
minor release is the o.s. if you just update certain packages (instead of taking
all avaailable updates)?

2) Can I apply package updates made in a minor release greater than my current
release without detriment to the integrity of the o.s.?
E.g. Suppose all my packages are at versions delivered in v5.6.
Suppose also, that I have a package xyz installed, and that an update to it was
made available in v5.8.
Can I upgrade xyz to the updated version from 5.8 without updating other
packages (except for any dependencies xyz has) to the versions available in
v5.8?

Thanks,
-- 
Jon Detert
Sr. Systems Administrator
Infinity Healthcare
Milwaukee, Wisconsin
414-290-6759

on 5/10/2012 1:14 PM Jon Detert spake the following:
> Two related questions about the minor release numbers (e.g. the 'x'
in 5.x or 6.x) :
> 
> 1) What constitutes the o.s. being at a particluar minor release? 
Typically, when you install you are getting a package set available from a
specific minor release number.  But what minor release is the o.s. at if I just
update the centos-release package, and no other package?  Typically, a 'yum
update' is said to take your whole package set to the latest minor release. 
But what minor release is the o.s. if you just update certain packages (instead
of taking all avaailable updates)?
> 
> 2) Can I apply package updates made in a minor release greater than my
current release without detriment to the integrity of the o.s.?
> E.g. Suppose all my packages are at versions delivered in v5.6.
> Suppose also, that I have a package xyz installed, and that an update to it
was made available in v5.8.
> Can I upgrade xyz to the updated version from 5.8 without updating other
packages (except for any dependencies xyz has) to the versions available in
v5.8?
> 
> Thanks,
The minor versions are only snapshots in time when install media is
re-generated... There is no good reason to stay on previous minor versions...
There is really only a 5 version or a 6 version... Staying with older packages
will only give you security problems...

On 05/11/2012 08:14 AM, Jon Detert wrote:
> Two related questions about the minor release numbers (e.g. the 'x'
in 5.x or 6.x) :
>
> 1) What constitutes the o.s. being at a particluar minor release? 
Typically, when you install you are getting a package set available from a
specific minor release number.  But what minor release is the o.s. at if I just
update the centos-release package, and no other package?  Typically, a 'yum
update' is said to take your whole package set to the latest minor release. 
But what minor release is the o.s. if you just update certain packages (instead
of taking all avaailable updates)?
>
> 2) Can I apply package updates made in a minor release greater than my
current release without detriment to the integrity of the o.s.?
> E.g. Suppose all my packages are at versions delivered in v5.6.
> Suppose also, that I have a package xyz installed, and that an update to it
was made available in v5.8.
> Can I upgrade xyz to the updated version from 5.8 without updating other
packages (except for any dependencies xyz has) to the versions available in
v5.8?
>
> Thanks,
This topic seems to arise often.
For my simple mind it works like this:
Lets say CentOS 6.0 is released - it is the base.
Various updates occur - yum update allows you to apply these to your system.
After a period - determined by our generous upstream benefactor - they 
decide to take a snap-shot of all the changes thus far, roll in a few 
more and call it version 6.1 and it becomes the new base. As time 
progresses the various "versions" are released, however they are
simply
a snapshot in time of all the various updates and patches to each of the 
rpms.
HTH