In message 
          RobH  wrote:

> On 08/11/2019 09:07, Mark J wrote:
>> In message 
>>            Chris Elvidge  wrote:
>>
>>> On 07/11/2019 12:52, RobH wrote:
>>>> I'm having a hard time finding the information I want , so I ask here:
>>>>
>>>> Has anyone had success using an external disk with the pi 4, and
>>>> preferably booting from it.
>>>>
>>>> The other option I thought about was to put some other version of Linux
>>>> on it, ubuntu?, but using etcher in linux doesn't do it, as it's an iso.
>>>>
>>>> Thanks
>>
>>> Not a Pi4 but I have Pi3+s booting from SD card (holding only the /boot
>>> partition) and 128/256Gb SSD (mSATA in mSATA to USB3 adapter) as root.
>>> Quite easy if you follow the instructions.
>>> I never had much luck booting directly from the USB SSD, hence the above
>>> arrangement.
>>
>> - but I, with an SSD and RPi3B+, via a mSATA to USB adapter, simply
>> 'burnt' the SSD with UbuntuMATE as if it were an SD card, and it all works
>> without the card installed. /With/ the card installed, the beast boots
>> from the card with the SSD still plugged in.
>>
>>

> An unrelated question:
> How did you get Ubuntu mate installed, as In tried and it didn't work.
> I downloaded the tar.gz file, then extracted the img file and the tried
> to burn it to an sd card with etcher. Etcher complained that it was not
> a bootable image. I tried again by clicking on the tar.gz file and Discs
> came up and said something about doing a restore. I selected the sdcard
> and clicked restore, but after inserting the sdcard into the pi, it
> didn't boot up.

I just use dd to burn the extracted image file running on the same
UbuntuMATE. I am nervous of the automatic Restore that Etcher seems to
want to do. Perhaps too easy to mess up your resident OS :-(

--
Mark J
From RISCOS 5.27 on a BeagleBoard-xM and Raspberry Pi2B
- and Linux on a PandaBoard ES and Raspberry Pi3B

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