[rhelv6-beta-list] My first experiences with RHEL6 beta

[R P Herrold]

On Wed, 16 Jun 2010, Bryan J. Smith wrote:

> Don't know why some people just ignore what LVM does, like allow
> people to exchange out disks/storage without having to take the
> system down.  Never said it is the end-all-be-all, but it does
> give you full control over your physical allocations, especially
> in the LVM2/DM flavor.
>
> I guess we just need the documentation to enlighten people then?  ;)

This misses the point.  It is not a lack of 'enlightenment' at 
all.  LVM is 'ignored' (removed from consideration, actually) 
because it tries to replace a robust and understood tool with 
a perhaps more capable one, at the expense of adding 
complexity to a system.  The 'value proposition' fails in 
readily understood use cases

- The older methods are almost self documenting on a single 
man page; in managing adding a new PV recently, I was toggling 
between several

- The older Linux config method of hanging a stated mountpoint 
on a stated partition of a stated drive is 'sed and awk' 
friendly for scripted management tools; the LVM method 
requires deeper knowledge of what is happening and is less 
well scriptable

- The older methods are more robust and less fragile.  In 
doing support, one needs a more complex environment to safely 
recover an arbitrary hosed LVM setup presented than the older 
methods.  Surely post call analysis on support issues within 
Red Hat shows that questions as to proper LVM usage greatly 
outnumber setting up an old form fstab; it sure does here

LVM may be the greatest thing since sliced bread, but it is 
and remains 'harder' and more fragile to recover from errors 
than its competitor

... and no amount of additional documentation or advocacy 
against 'ignorance' can change that

-- Russ herrold