How to use this partition for a persistent install?
You can do it 'manually' at boot by adding the boot option persistent, but it is not very convenient.
You can edit the system part of the USB boot drive to include the boot option persistent. Then you get a system that will be persistent live automatically.
You can edit the iso file with a binary editing method as described at the following links,
You can extract the content of the iso file and after that edit the file grub.cfg according to the following link,
help.ubuntu.com/community/Installation/iso2usb/diy
Also a 64GB flash drive would allow over 60GB of persistence which seems a bit much.
Is it possible to convert some of this space to a NTFS data partition?
- You can do it in a procedure in several steps, if you have/make only one Ubuntu system (the persistent live USB pendrive) with the cloning method. But it will be complicated, and not recommended for beginners, because you cannot use the most user friendly tool,
gparted.
Otherwise, if you have another Ubuntu system, you can do it when you make an extracted system according to the previous link. In this case it can be convenient to use gparted to edit partitions and to create file systems,
- a
casper-rw partition with ext2 or ext4 for persistence
- a
home-rw partition with ext2 or ext4 for persistence of the home directory (optional)
- a
usbdata partition with NTFS for exchange of data with Windows
- This is home territory for mkusb. This tool lets you split the available drive space between a
casper-rw partition and a usbdata partition automatically.
If you are happy with converting all of this space to an NTFS data partition, you can do it manually also with a cloned system and test it with the following steps,
Make a live-only drive with any cloning tool, for example the Ubuntu Startup Disk Creator or Win32 Disk Imager.
Boot into it without any [manually added] boot option and let it create a casper-rw partition automatically.
Reboot into it, this time with the boot option nopersistent and reformat the casper-rw partition to a usbdata partition with NTFS.
Checking: Reboot into it again without any [manually added] boot option , this time to mount the usbdata partition and write a small 'Hello World' file.
echo 'Hello World' > hello.txt
Checking: Boot into Windows, plug in the USB drive and read the small 'Hello World' file.
Please notice that without any casper-rw (and maybe home-rw) partition modifications of the Ubuntu system will not persist shutdown and reboot. In that context it is a live-only drive, where you can use the drive space behind the system to store data and exchange data with other systems, also Windows systems.
Step #3 and the command to create the NTFS file system is crucial:
xubuntu@xubuntu:~$ sudo mkfs.ntfs -f -L usbdata /dev/sdb3
Cluster size has been automatically set to 4096 bytes.
Creating NTFS volume structures.
mkntfs completed successfully. Have a nice day.
xubuntu@xubuntu:~$ sudo partprobe
Warning: The driver descriptor says the physical block size is 2048 bytes, but Linux says it is 512 bytes.
xubuntu@xubuntu:~$ sudo lsblk -fm
NAME FSTYPE LABEL UUID FSAVAIL FSUSE% MOUNTPOINT SIZE OWNER GROUP MODE
loop0 squashfs 0 100% /rofs 1.4G root disk brw-rw----
sda 119.2G root disk brw-rw----
├─sda1 ntfs System 3AA4725CA4721B19 500M root disk brw-rw----
├─sda2 ntfs Windows 786274A362746830 117.8G root disk brw-rw----
└─sda3 ntfs Recovery AAD474DDD474ACE7 1000M root disk brw-rw----
sdb iso9660 Xubuntu 19.10 amd64 2019-10-17-12-50-28-00 14.9G root disk brw-rw----
├─sdb1 iso9660 Xubuntu 19.10 amd64 2019-10-17-12-50-28-00 0 100% /cdrom 1.5G root disk brw-rw----
├─sdb2 vfat Xubuntu 19.10 amd64 866D-0A62 3.9M root disk brw-rw----
└─sdb3 ntfs usbdata 69F25A82472A1E2C 13.4G root disk brw-rw----
xubuntu@xubuntu:~$ cat /proc/cmdline
BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/xubuntu.seed quiet splash nopersistent ---
xubuntu@xubuntu:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 19.10
Release: 19.10
Codename: eoan
xubuntu@xubuntu:~$
