bootable ext. USB SSD for backup

[Mehmet Erol Sanliturk]

On Thu, Mar 16, 2017 at 12:46 PM, Matthias Apitz <guru at unixarea.de> wrote:

>
> Hello,
>
> I have acquired a small and flat USB 3.0 external disk (must be SSD for
> the size of the case):
>
> Mar 16 19:36:54 c720-r314251 kernel: da0: <TOSHIBA External USB 3.0 5438>
> Fixed Direct Access SPC-4 SCSI device
> Mar 16 19:36:54 c720-r314251 kernel: da0: Serial Number 20170114010787F
> Mar 16 19:36:54 c720-r314251 kernel: da0: 40.000MB/s transfers
> Mar 16 19:36:54 c720-r314251 kernel: da0: 953869MB (1953525164 512 byte
> sectors)
> Mar 16 19:36:54 c720-r314251 kernel: da0: quirks=0x2<NO_6_BYTE>
>
> Ofc it has not the promised 1 TB volume, just only 953869 MB, i.e. only
> 1 Marketing-TB;
>
> I'm thinking in re-partitioning the disk (which is actual only one big
> NTFS slice) with gpart(8), install even a kernel into a small FS at the
> beginning and keep the rest as a big UFS for backups. Having it bootable
> with a system could be handy if one has to rescue a system and restore
> the last dunp.
>
> Any ideas/comments
>
>         matthias
> --
> Matthias Apitz, ✉ guru at unixarea.de, ⌂ http://www.unixarea.de/  ☎
> +49-176-38902045
> _______________________________________________
>
>

I am sorry to respond with respect to Linux . I think that FreeBSD will be
a little similar .


When NTFS external disk is used , it is not necessary to "mount" it : It is
directly handled with LOSS of access right information of files .


When a Linux file system is used , it is necessary to "mount" it for using
it . You need to use it either as "root" or find a way to use it as a
"user" .


If it is bootable , with respect to my use of Fedora ( it may depend on
version ) , booting is starting from external drive , but somewhere there
is a "fixed" or "hard-coded" sda , etc. . When it is encountered , booting
is switching to internal HDD . To prevent this switching , it is necessary
to disconnect power of internal HDD units .


The above issues are possible difficulties .


Mehmet Erol Sanliturk