On Sat, 26 Sep 2015, Anton Aylward wrote:
LVM is a storage manager. You can think of it as a substitute for partitioning. If you partition with the conventional tools like fdisk and family then the partitions are 'hard', they are at the BIOS level. While there are kludges like gparted, the concept is that you manage the hard partitions outside of the OS,
Granted that most of us do use fsisk to partition, perhaps as BOOT, SWAP and now since grub/grub2 can handle it, put everything else in a LVM logical partition, which is 'software defined'.
Okay but it is a bit the same as software raid (md...). And likewise it has great advantage if also detriments. You raid system is inherently less secure because you need to know all the tools by heart. At the same time you can mix raid levels at will. You can't do that with just hardware raid. (And then many hardware raid solutions depend on a Windows driver, making them software raid regardless X-(.
Oh, right, its a trend; its sort of a virtualization of disk space, like we have virtual networks . Many people feel its humbug and I can't blame them; its certainly 'deferred design'.
You have a point there. But it is the same also as with RAID, the system is more vulnerable. Like, making snapshots just for backups.... it is not my cup of tea really. Why am I using it? It feels like a sacrifice. I am sacrificing safety because now I am using a storage manager (partition manager) to create partitions that hardly exist for more than 30 minutes. It can be mitigated a bit with sufficient level of "protection" against erroneous commands. Just wrap your common tasks into scripts or functions that do just that and nothing else so you can't be making any mistakes. The more something can be done e.g. with BIOS "MENU" tools the better you are off. Failsafe, easy, user interface, not needing any workable system. But it's not like I really see an alternative at this point.
But LVM is NOT, repeat NOT, a file system.
Aye aye.
Contrariwise BtrFS *is* a storage manager, a complete storage manager. All the way down from file to device layout management. You *can* put it on a disk with no partitioning and it manages the space and delivers the file system view. It reminds me of the old (but still in use) IBM CICS, where everything was within CICS, teleprocessing (what we think of as telnet, ssh), data transfer (what we think of as UUCP or FTP) database management and more.
I read that yes. Seems rather very very scary ;-). To me at least.
With LVM you can choose what file system goes into the logical partitions. There is no such analogue for BtrFS. One <strike>Ring</strike> filesystem to rule them all. And its assimilating like the Borg.
I was on Kubuntu forums the other day fighting the venerable Steve Riley about this. He works for Amazon. Cloud. It couldn't get any of this through to him. He kept insisting that BtrFS would never put me in a position where I would be disenfranchised because I would end up in a world where BtrFS would be the all and everything. Basically he just didn't see that as a problem. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org