About partitioning

satimis · 12-27-2012, 09:49 AM

Hi all,

Ubuntu 12.04 desktop 64bit

I selected manual partioning and selecting logical on;

/boot
/root
swap

However after reboot I can't find LV;

$ sudo fdisk -l

Code:

[sudo] password for satimis: 

Disk /dev/sda: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0008f463

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      976895      487424   83  Linux
/dev/sda2          978942  2930276351  1464648705    5  Extended
/dev/sda5          978944  2911133695  1455077376   83  Linux
/dev/sda6      2911135744  2930276351     9570304   82  Linux swap / Solaris

I tried 3 times with the same result. I also tried not selecting /boot logical

Please help. Whether HD exceeding 1TB can't partitioned as LV?

TIA

B.R.
satimis

johnsfine · 12-27-2012, 10:09 AM

Quote:

Originally Posted by satimis

selecting logical on;
...
However after reboot I can't find LV;

I assume by "LV" you mean LVM.

"Logical" in setting up partitions does NOT mean LVM.

I've never used LVM, so I can't give you detailed instructions. I used a quick google search to try to find your answer, and found a list of guides for Ubuntu LVM for various advanced situations:
https://help.ubuntu.com/community/In...llation_Guides

I didn't find any instruction for Ubuntu LVM installation for the simplest case, which you seem to need. But I didn't search very hard and I expect the instructions are out there if you put a little effort into looking.

satimis · 12-27-2012, 10:15 AM

Quote:

Originally Posted by johnsfine

I assume by "LV" you mean LVM.

"Logical" in setting up partitions does NOT mean LVM.

I've never used LVM, so I can't give you detailed instructions. I used a quick google search to try to find your answer, and found a list of guides for Ubuntu LVM for various advanced situations:
https://help.ubuntu.com/community/In...llation_Guides

I didn't find any instruction for Ubuntu LVM installation for the simplest case, which you seem to need. But I didn't search very hard and I expect the instructions are out there if you put a little effort into looking.

Thanks for your advice.

I'm a little bid confused. I'm now on another Ubuntu box;

Ubuntu 12.04 desktop 64bit

$ sudo fdisk -l

Code:

Disk /dev/sda: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00064d3a

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      499711      248832   83  Linux
/dev/sda2          501758  3907028991  1953263617    5  Extended
/dev/sda5          501760  3907028991  1953263616   8e  Linux LVM

Disk /dev/mapper/ubuntu-root: 1991.7 GB, 1991682031616 bytes
255 heads, 63 sectors/track, 242141 cylinders, total 3890003968 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/ubuntu-root doesn't contain a valid partition table

Disk /dev/mapper/ubuntu-swap_1: 8317 MB, 8317304832 bytes
255 heads, 63 sectors/track, 1011 cylinders, total 16244736 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/ubuntu-swap_1 doesn't contain a valid partition table

The output is completely different showing /dev/mapper. The command is the same "sudo fdisk -l"

satimis

johnsfine · 12-27-2012, 10:26 AM

Your second system has one LVM partition (which seems to be what you want for your first system, but don't know the right steps during install). Inside that LVM partition it has swap and root.

Quote:

Originally Posted by satimis

The output is completely different showing /dev/mapper. The command is the same "sudo fdisk -l"

The command is the same. The output is different because the partitioning is different. The second system has /dev/mapper pseudo disks and the first system doesn't.

It appears that fdisk -l is an obsolete tool when you have LVM. The information fdisk -l gives you for that second system is a bit misleading, especially the part

Quote:

doesn't contain a valid partition table

For things that aren't supposed to contain partition tables.

If I understand correctly, GRUB does not understand LVM, so when you are using LVM you need a /boot partition outside the LVM (as that second system has) and then typically you put all your other "partitions" inside the LVM (But those aren't really partitions. They just act like partitions).

In your other thread, I said that I don't normally advise making /boot separate from root. That applies to the simple cases in which GRUB can read your root partition. If you have root inside LVM and/or one of the forms of RAID that GRUB can't read, then obviously /boot must be separate from root.

widget · 12-27-2012, 10:09 PM

Also on your first post I don't believe you have LVM.

You have an extended partition, sda2 and within it sda5 and sda6 (swap).

That looks like a typical extended partition with 2 logical partitions such as you would have with / on sda1 and /home on sda5.

All logical partition numbers always start with 5 in case you were wondering.

satimis · 12-27-2012, 10:23 PM

Hi all,

Thanks for your advice.

I made a mistake not using the Alternative Installer installing the new PC additionally selecting manual partitioning. I couldn't create LVM partitions.

I'll reinstall the PC running the Aternative Installer. Also I'll partition /boot outside LVM

satimis