Re: Correct fdisk info for ext2fs?

On Thu, May 30, 2024, at 6:02 PM, nisp1953 wrote:
> OpenBSD 7.5 GENERIC.MP#82 amd64
>
> Hi all:
>
> I formatted a 2TB USB Hard Drive under Linux and get the following from fdisk:
>
> # fdisk sd1
> Disk: sd1 geometry: 243201/255/63 [3907029167 Sectors]
> Offset: 0 Signature: 0x0
> Starting Ending LBA Info:
> #: id C H S - C H S [ start: size ]
> -------------------------------------------------------------------------------
> 0: 00 0 0 0 - 0 0 0 [ 0: 0 ] Unused
> 1: 00 0 0 0 - 0 0 0 [ 0: 0 ] Unused
> 2: 00 0 0 0 - 0 0 0 [ 0: 0 ] Unused
> 3: 00 0 0 0 - 0 0 0 [ 0: 0 ] Unused
>
> I had to add a disklabel before I could mount it and use it on OpenBSD:
> # disklabel sd1
> # /dev/rsd1c:
> type: SCSI
> disk: SCSI disk
> label: BUP Slim
> duid: 3cca86bd1e312e1f
> flags:
> bytes/sector: 512
> sectors/track: 63
> tracks/cylinder: 255
> sectors/cylinder: 16065
> cylinders: 243201
> total sectors: 3907029167
> boundstart: 0
> boundend: 3907029167
>
> 16 partitions:
> # size offset fstype [fsize bsize cpg]
> c: 3907029167 0 unused
> i: 3907029167 0 unknown
>
> It does have an signed DUID:
> # sysctl hw.disknames
> hw.disknames=sd0:c9251986e646484c,sd1:3cca86bd1e312e1f
>
> I have been using it for several days and I write to it both under
> Linux and OpenBSD.
> What am I doing wrong here that no partitions show un in fdisk?
> Here is the relevant dmesg info:
> scsibus4 at umass0: 2 targets, initiator 0
> sd1 at scsibus4 targ 1 lun 0: <Seagate, BUP Slim, 1708>
> serial.0bc2ac300000NAEA4KVV
> sd1: 1907729MB, 512 bytes/sector, 3907029167 sectors
> /dev/sd1i: file system not clean; please fsck(8)
>
> Thanks in advance for any advice on this.

It looks like you have formatted an entire drive without partitioning it first. This isn't wrong *per se*, in the same way you might format certain types of external media without partitioning them, but it's not expected and could become a footgun if you go to perform an operation on the drive and forget that it isn't a filesystem within a partition. As you've noted, it does operate correctly.

Brian Conway
Owner
RCE Software, LLC