[Mageia-dev] time to switch from raw partitions to lvm?

[Thierry Vignaud]

On 24 February 2011 06:06, andre999 <andr55 at laposte.net> wrote:
>> It's not as easy as LVM (need to use a partitionner).
>> Diskdrake and the like will force you to umount the partitions to resize
>> which may needs to boot on a rescue CD (eg for resizing / fs)
>> It may not be possible ie:
>
> A rescue CD like Sysrescuecd is easy to use and comes with all the tools
> needed.
> It would be nice if the rescue option of the eventual release Mageia dvds
> contained the few utilities necessary for this.

that's not the point: you still have to reboot in order to resize some
fs whereas,
at least you have to umount them with graphical tools.
whereas with lvm you can resize fs online, without umounting anything, without
rebooting;.

>> - you already have 4 primary partitions and none of them is an extended
>> one.
>
> A gpt partition table solves this problem.

which nearly nobody use, hence it's irrelevant.
The 99.99% of users who are using partitions are still stuck with the problem.

>> - If you've a small 8Go partition at start of the disk followed by one
>> To partition
>>   and you want to increase the first one, you're screwed without LVM
>>   With LVM, you can just got some free space from anywhere (even another
>> disk)
>
> You can do that with symbolic links if you don't want to resize the
> partitions.

quick & dirty workaround. hardly a real solution...
and if you have one directory that is too big to move in any of the
available partition,
you are still stuck, whereas with lvm you can shrunk every fs and the
all all of the small
space just freed into the fs that needs it

>> - one can live resize (w/o umouting/remounting)
>>
>> - one can use snapshots in order to rollback dangerous update
>>   (eg: for trying initscript ->  systemd switch, ...)
>>
>> I think it brings many usefull features.
>> Those who don't want LVM could still do manual partitionning.
>
> These seem to be mostly enterprise-oriented factors, unless I'm missing
> something.
> For now at least, I prefer manual partitionning to be the default.

easy rollbacking after a disastrous update to a new xserver, a new
boot system, ...
is appealing for cooker users.

live resizing for freeing space in order to set up a vm on top of block device
(yes you can still use a file loopback but this is cleaner)

being able to live resizing fs in order to move free space where it's
needed before
eg: doing a big backup, copying those 3 dvds of the mariage the wife wants to be
saved, ... without rebooting is appealing to anyone