LVM

can someone recommend me a very good site that talk about LVM, for example :

it will talk about

1. volume group (VG)
2. physical volume (PV)
3. logical volume (LV)
4. physical extent (PE)
5. logical extent (LE)

most important of all, a comprehensive guide on how to create them.

Thanks.
LVL 9
binary_1001010Asked:
Who is Participating?
 
xDamoxCommented:
0
 
binary_1001010Author Commented:
i dont understand what is physical/logical extent.

I heard about 4mb entent, 88 extents...etc...

if i got a 200GB of hard disk. what does this extent mean to me?

Thanks.
0
 
xDamoxCommented:
Hi,

With partition in Linux you can have a total of 4 physical partitions. However you may want more partitions
so you are require to use logical extentions e.g.


/                  <--- Physical
/home        <--- Physical
/usr            <--- Physical
/opt           <---- Physical

Now you need to create a logical partitions if you want more

/usr/local <-- Logical

so your whole layout should be like:


/                  <--- Physical
/home        <--- Physical
/usr            <--- Physical
/opt            <---- Physical
/usr/local  <-- Logical
0
 
binary_1001010Author Commented:
but that doesn't explain what 4mb extent(the default) mean.
that also doesn't explain the size of the extent vs the number of extents.

if i got 200 gb of HDD, does that mean 200,000 divide 4mb = 50000 extents
i can have 50,000 extents?
0
 
xDamoxCommented:
Hi,

Behind the scenes, the LVM system allocates storage in equal-sized "chunks", called extents. We can specify the particular extent size to use at volume group creation time. The size of an extent defaults to 4Mb, which is perfect for most uses. One of the beauties of LVM is that the physical storage locations of the extents used for one of our logical volumes (in other words, what disk they're stored on) can be dynamically changed while our logical volume is mounted and in use! The LVM system ensures that our logical volumes continue to operate perfectly while allowing the administrator to physically change where everything is stored.
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.