gparted output different from fdisk when cp iso to usb

colorpurple21859 · 07-20-2019, 10:31 PM

put iso on usb with this

Code:

cp some.iso /dev/sdb
sync

gparted only shows this: /dev/sdb iso9660 14.61GB

fdisk output

Code:

Disk model: USB Flash Drive 
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: dos
Disk identifier: 0x00000000

Device     Boot Start      End  Sectors  Size Id Type
/dev/sdb1  *       64    10371    10308    5M 83 Linux
/dev/sdb2       10372    16131     5760  2.8M ef EFI (FAT-12/16/32)
/dev/sdb3       16384 30629375 30612992 14.6G 83 Linux

I added the third partition with cfdisk, but when I run mkfs.ext4 I get /dev/sdb3 doesn't exist.

linus72 · 07-21-2019, 05:32 AM

I noticed same when comparing dd to cp on iso's I make
weird huh?

hey did you use gparted to make the unused/unallocated part a filesystem?
On my usb I cp'd to usb, then used gparted to make smaller the unallocated part to just where the efi/5M first partition is then created sdb3 as either fat32 or ext4

so, resize it so that sdb1 is 5M, efi is 2,8M as yours, so resize to 7.8 or 8M, then format rest as sdb3
hold on I'll show a picture

syg00 · 07-21-2019, 06:07 AM

So what's wrong with using "dd" ?.

colorpurple21859 · 07-21-2019, 06:44 AM

Quote:

hey did you use gparted to make the unused/unallocated part a filesystem?

No, used cfdisk, gparted shows only one partition as iso9660. Last night mkfs would give /dev/sdb3 doesn't exist. This morning mkfs worked, yes I did a reboot last night. Parted and fdisk show 3 partitions, gparted only 1 iso9660 partition.

Quote:

So what's wrong with using "dd" ?.

Not looking for a solution for the usb, just an observation.

ehartman · 07-21-2019, 09:32 AM

Quote:

Originally Posted by colorpurple21859

gparted shows only one partition as iso9660.

So probably the iso got its own gpt partition table and cfdisk shows the "legacy" (cq MBR) one. And they are not in accord.