On Thu, 8 Jan 2015 09:49:19 +0000 Mark Rogers mark@more-solutions.co.uk wrote:
On 7 January 2015 at 16:57, steve-ALUG@hst.me.uk wrote:
gparted and fdisk spring to mind.
I also find "file -s" to be useful, as in: sudo file -s /dev/sdc*
One thing I have noted is that sometimes USB sticks get formatted without a partition table (ie /dev/sdX is formatted rather than /dev/sdX1, and the latter therefore does not exist). Not everything supports this.
I have now identified the problem. The 'working' stick is formatted to MBR whereas the non-working sticks i.e. not seen by my car but functioning as normal in any computer I've tried, have GUID partition table.
The partitions are as you would expect. To fix the problem I did a google search for 'convert gpt to mbr' and after a bit of a struggle (there was more struggle trying to find a solution than actually doing the conversion), my car now recognises one of the sticks. I've only tried one in the car as it was late and didn't want to disturb my neighbours by having music blasting out of the audio system. I'll try the second one today.
As I like to be able to see all my files and do any work from anywhere i.e. both linux and Windows, I tried converting the second stick on my wife's Windows 8.1 laptop. Using similar commands to linux I was able to convert that one using a command called diskpart. That's the one I have yet to try in the car.
Also worth noting is that you can copy the partition table from one device (assuming it has one!) to another with: sudo sfdisk -d /dev/sdX | sudo sfdisk /dev/sdY .. substituting X and Y as appropriate.
If I copy the partition table, do I end up with two sticks with the same volume name? I realise I could easily edit that post-copy, but just wondering.
Thanks to you both for your thoughts and suggestions.