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I normally use fdisk -l to look at partitions. I recently installed ubuntu 17.10 on a computer, and noticed that fdisk is not showing me the boot flag as it used to do. The output now looks for example like this

Device       Start        End    Sectors  Size Type
/dev/sda1     2048    1050623    1048576  512M EFI System
/dev/sda2  1050624 1953523711 1952473088  931G Linux filesystem

I've not been able to find any info on why the boot column is missing, or how to get it back. Any links/info on this?

fdisk --version gives me fdisk from util-linux 2.30.1. I have another computer with version 2.27 (ubuntu 16.04), and this does show me the boot flag.

  • Mine the same never paid attention until you mentioned this! – George Udosen Dec 4 '17 at 17:16
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    I think it is because of GPT - do you have line "Disklabel type: gpt" in the start of fdisk -l output? – N0rbert Dec 4 '17 at 17:20
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    @N0rbert yes I do! – George Udosen Dec 4 '17 at 17:33
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    I have GPT too, so I think it is normal for non-MBR partitioning (sda1 is EFI, no active flag). – N0rbert Dec 4 '17 at 17:37
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This is because of GPT.

On my Ubuntu 16.04 LTS system fdisk -l /dev/sda shows the following:

Disk /dev/sda: xxx GiB, yyyyyyyyyyyyy bytes, zzzzzzzzz 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
**Disklabel type: gpt**
Disk identifier: AAAAAAAA-BBBB-CCCC-DDDD-EEEEEEEEEEEE

Device         Start       End   Sectors   Size Type
/dev/sda1       2048    616447    614400   300M EFI System
...

But sudo parted /dev/sda shows almost the same:

(parted) p
Model: ATA ... (scsi)
Disk /dev/sda: xxxGB
Sector size (logical/physical): 512B/512B
**Partition Table: gpt**
Disk Flags: 

Number  Start   End     Size    File system     Name                          Flags
 1      1049kB  316MB   315MB   fat32           EFI system partition          **boot**, esp
...

So parted correctly shows boot flag.

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