boot - USB persistence not working

I would like to create an Ubuntu live usb with persistence. With Linux Tails it was working well for me without problem but for Ubuntu and Mint I have some problems.

I tried to use rufus, unetbootlin and so on from Windows and mkusb from Linux.I always ended up with the following:

I have a casper-rw partition which is not writable after boot by default (after chmod777 it is writeable).
When I am booting in grub I never see persistence in the parameter list (on partition 4 -  see partition description little later). I tried to add it there but system become unstable and haven't saved any changes I made like it is a live boot.

Last time I used mkusb. It looks that everything went OK (there were no errors in the console). I see new2 boot options in the BIOS.

bios picture

If I choose the partition 3 than it does nothing, only black screen and nothing happens. If I boot with the partition 4 than I can see a "usbboot" partition as partition 3. On that I see a grub.cfg which looks good, there is persistence and so on in the file. 

Gparted info about pendrive

If I choose the partition 4 for boot than it boots without any persistent (looks like this is the live usb image)

Can you please help me to fix this issue?

Do I have to activate persistence storage somehow like in the TAILS Linux?
If you need any further details please let me know.

If you use a casper-rw persistent partition on the same drive you're booting from with anything but (the yet to be released) Ubuntu 19.10, you're going to be screwed because of Ubuntu/casper bug #1489855. And I'm afraid that, since Mint is a derivative of Ubuntu, it suffers from the same casper bug. At this stage, I'm not aware of any distro having backported the fix for #1489855 into an updated release.

So here's what I would recommend:

• Download the latest daily-live of Ubuntu 19.10 and use that with Rufus 3.8 or later. It should work just fine for persistence (source: I am the developer of Rufus, and I have tested it fairly extensively to make sure that it does work).



• Use Debian or a Debian derivative that doesn't use casper-rw for persistence. For instance, there again, Debian Live 10.x should work just fine for persistence with Rufus 3.8 or later.


• Wait until the Mint distro maintainers pick the casper fix and produce a release that is not plagued by bug #1489855 and can therefore properly support persistent partitions.

I spent a lot of time ensuring that Rufus can automate the hard work for you (again, provided that the distro you use isn't plagued with a major bug with regards to persistent partition support), and you indicated that you tested Rufus. So you might as well let it sort your issue for you, by using it with an ISO that actually has a chance to work...