On Saturday 09 April 2011 06:43:25 Dale wrote: > Alan McKinnon wrote: > > Apparently, though unproven, at 12:48 on Saturday 09 April 2011, Dale > > did > > opine thusly: > > Yes. > > > > PVs, VGs, LVs all have a concept of extend|resize|reduce. What that > > means > > depends on what you are working with, but they all make the thing bigger > > or smaller. > > > > For a PV it means the underlying device's size changed, so the PV must > > change to match. Take a 500G drive, create 1 partition on it of 100G > > and make it a PV. Now enlarge the partition to 200G, you must extend > > the PV to match. > > > > A VG isn't a single thing, it's a collection of things. Extending it > > means to add more PVs, reducing it means to take PVs out of the VG. > > Hopefully you will always remember to migrate the data off a PV before > > removing it from a VG :-) > > > > Extend/Reduce an LV means to make the device larger/smaller. It is > > exactly the same thing as changing a partition size using fdisk. > > Obviously, you need to tweak the filesystem at the same time > > So, when I get me a new drive, I use pvcreate to get it ready for LVM, > then use vgextend to add it to the VG, then it is available for whatever > LV I want to extend or to make a new LV? > > I think I am catching on here. It was just difficult for me to grasp > how things are layered for some reason. Some of the pictures I found > helped a good bit tho. Just helped me picture what the commands are > doing exactly. > > I did learn the hard way to resize the file system tho. I forgot that > earlier. Sort of had me scratching my head for a bit. lol
That's an easy one to miss :) You do seem to be catching on quick on this. -- Joost
