How to make an external hard drive bootable with unetbootin?

Question

The SATA hdd is connected with a USB adapter cable.

How is unetbootin used to write an ISO image:

to an external hard drive for installing Ubuntu?

It's not clear that unetbootin is listing the external hard drive, which is connected from a USB to SATA adapter, as a USB type media.

(parted)                                                                  
(parted) print devices                                                    
/dev/sda (1000GB)
/dev/sdb (360GB)
/dev/mapper/vgubuntu-swap_1 (1023MB)
/dev/mapper/vgubuntu-root (999GB)
(parted)                                                                  
(parted) q                                                                
nicholas@mordor:~$ 
nicholas@mordor:~$ sudo fdisk -l
Disk /dev/loop0: 138.81 MiB, 145534976 bytes, 284248 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop1: 150.4 MiB, 157327360 bytes, 307280 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop2: 138.92 MiB, 145645568 bytes, 284464 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop3: 150.1 MiB, 157298688 bytes, 307224 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop4: 99.22 MiB, 104030208 bytes, 203184 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop5: 99.15 MiB, 103964672 bytes, 203056 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop6: 55.48 MiB, 58159104 bytes, 113592 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop7: 55.46 MiB, 58142720 bytes, 113560 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/sda: 931.53 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: WDC WD10EADS-00P
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x8b0be982
Device     Boot   Start        End    Sectors  Size Id Type
/dev/sda1  *       2048    1050623    1048576  512M  b W95 FAT32
/dev/sda2       1052670 1953523711 1952471042  931G  5 Extended
/dev/sda5       1052672 1953523711 1952471040  931G 8e Linux LVM
Disk /dev/mapper/vgubuntu-root: 930.6 GiB, 998638616576 bytes, 1950466048 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/vgubuntu-swap_1: 976 MiB, 1023410176 bytes, 1998848 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop8: 125.87 MiB, 131960832 bytes, 257736 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop9: 131.61 MiB, 137990144 bytes, 269512 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop10: 105.88 MiB, 111001600 bytes, 216800 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop11: 128.27 MiB, 134492160 bytes, 262680 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop12: 162.89 MiB, 170778624 bytes, 333552 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop13: 217.92 MiB, 228478976 bytes, 446248 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop14: 218.102 MiB, 229629952 bytes, 448496 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop15: 64.36 MiB, 67477504 bytes, 131792 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop16: 64.79 MiB, 67915776 bytes, 132648 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop17: 101.101 MiB, 106938368 bytes, 208864 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop18: 19.9 MiB, 20840448 bytes, 40704 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop19: 462.59 MiB, 485044224 bytes, 947352 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop20: 470.51 MiB, 493355008 bytes, 963584 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop21: 65.32 MiB, 68489216 bytes, 133768 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop22: 65.31 MiB, 68476928 bytes, 133744 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop23: 29.16 MiB, 30568448 bytes, 59704 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop24: 29.28 MiB, 30695424 bytes, 59952 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop25: 51.2 MiB, 53501952 bytes, 104496 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop26: 51.4 MiB, 53522432 bytes, 104536 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop27: 32.28 MiB, 33841152 bytes, 66096 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop28: 32.28 MiB, 33841152 bytes, 66096 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/sdb: 335.36 GiB, 360080694272 bytes, 703282606 sectors
Disk model: Storage Device

Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xa4c751ab
Device     Boot     Start       End   Sectors   Size Id Type
/dev/sdb1  *         2048 694882303 694880256 331.4G 83 Linux
/dev/sdb2       694884350 703281151   8396802     4G  5 Extended
/dev/sdb5       694884352 703281151   8396800     4G 82 Linux swap / Solaris
nicholas@mordor:~$ 
nicholas@mordor:~$ mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=3973980k,nr_inodes=993495,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=801120k,mode=755)
/dev/mapper/vgubuntu-root on / type ext4 (rw,relatime,errors=remount-ro)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
none on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=16508)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
/var/lib/snapd/snaps/chromium_1557.snap on /snap/chromium/1557 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/chromium_1558.snap on /snap/chromium/1558 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/codium_157.snap on /snap/codium/157 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/codium_162.snap on /snap/codium/162 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/core_10908.snap on /snap/core/10908 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/core_10958.snap on /snap/core/10958 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/core18_1997.snap on /snap/core18/1997 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/docker_471.snap on /snap/docker/471 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/docker_796.snap on /snap/docker/796 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/electrum_2.snap on /snap/electrum/2 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/geth_477.snap on /snap/geth/477 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-28-1804_145.snap on /snap/gnome-3-28-1804/145 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/core18_1988.snap on /snap/core18/1988 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-34-1804_60.snap on /snap/gnome-3-34-1804/60 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gnome-3-34-1804_66.snap on /snap/gnome-3-34-1804/66 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gtk-common-themes_1513.snap on /snap/gtk-common-themes/1513 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/gtk-common-themes_1514.snap on /snap/gtk-common-themes/1514 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/ipfs-desktop_24.snap on /snap/ipfs-desktop/24 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/libxml2_69.snap on /snap/libxml2/69 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/netbeans_41.snap on /snap/netbeans/41 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/netbeans_45.snap on /snap/netbeans/45 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/powershell_160.snap on /snap/powershell/160 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/ruby_201.snap on /snap/ruby/201 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/ruby_212.snap on /snap/ruby/212 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snap-store_498.snap on /snap/snap-store/498 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/powershell_158.snap on /snap/powershell/158 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snap-store_518.snap on /snap/snap-store/518 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snapd_11402.snap on /snap/snapd/11402 type squashfs (ro,nodev,relatime,x-gdu.hide)
/var/lib/snapd/snaps/snapd_11588.snap on /snap/snapd/11588 type squashfs (ro,nodev,relatime,x-gdu.hide)
/dev/sda1 on /boot/efi type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
tmpfs on /run/snapd/ns type tmpfs (rw,nosuid,nodev,noexec,relatime,size=801120k,mode=755)
nsfs on /run/snapd/ns/docker.mnt type nsfs (rw)
nsfs on /run/snapd/ns/snap-store.mnt type nsfs (rw)
nsfs on /run/snapd/ns/ipfs-desktop.mnt type nsfs (rw)
tmpfs on /run/user/125 type tmpfs (rw,nosuid,nodev,relatime,size=801116k,mode=700,uid=125,gid=130)
gvfsd-fuse on /run/user/125/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=125,group_id=130)
tmpfs on /run/user/1003 type tmpfs (rw,nosuid,nodev,relatime,size=801116k,mode=700,uid=1003,gid=1003)
gvfsd-fuse on /run/user/1003/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1003,group_id=1003)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=801116k,mode=700,uid=1000,gid=1000)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
/dev/sdb1 on /media/nicholas/3e798148-4333-4add-ba6c-f4272c17263e type ext4 (rw,nosuid,nodev,relatime,uhelper=udisks2)
nicholas@mordor:~$ 
nicholas@mordor:~$ lsusb
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 013: ID 1c4f:0034 SiGma Micro Usb Mouse
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 003: ID 14cd:6116 Super Top M6116 SATA Bridge
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 002: ID 2a7a:6a18 CASUE CASUE USB Keyboard
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
nicholas@mordor:~$ 
nicholas@mordor:~$ ls /media/nicholas/
3e798148-4333-4add-ba6c-f4272c17263e
nicholas@mordor:~$ 
nicholas@mordor:~$

Perhas the external drive needs to formatted to FAT32?

You just asked this 40 mins ago do not post another question edit the first one. — David, Apr 22 '21 at 05:35
Does this answer your question? How to install Ubuntu from an external hard drive connected with a SATA to USB adapter cable? — David, Apr 22 '21 at 05:35
Possibly, @David I selected the USB option with unetbootin and proceeded from there. About to reboot and try to boot from the USB drive. We shall see. — Nicholas Saunders, Apr 22 '21 at 05:47
well, wasn't able to boot either from the USB external hdd nor from the internal hdd. So, not sure how precisely to use unetbootin in this scenario. — Nicholas Saunders, Apr 22 '21 at 07:04
@David: Your link points to an unanswered question, I don't see how it would help answer this one.. — C.S.Cameron, Apr 22 '21 at 07:49
@Nicholas Saunders UNetbootin will not create a Live or Persistent USB on an external hard drive. Both Rufus and Etcher can create live and persistent external or internal hard drives, however is that what you really want? Or do you want to fully install to the external drive just like to an internal drive? I will post the advantages of each. — C.S.Cameron, Apr 22 '21 at 08:00
if unetbootin won't make an external SATA hdd (connected with USB cable) bootable, then the q is unanswerable @C.S.Cameron -- but that seems odd. I'd be more interested in a "live" option. — Nicholas Saunders, Apr 22 '21 at 08:08
@Nicholas Saunders give me a few minutes and I will post an answer for that using Rufus, (persistent) or Etcher, (Live only). — C.S.Cameron, Apr 22 '21 at 08:12

C.S.Cameron · Answer 1 · 2021-04-22T08:58:04.603

4

Live External HDD using balenaEtcher

Download Etcher: https://www.balena.io/etcher/ , There are Windows and Linux versions available.
Double click .exe file to open.
Select settings, the cog icon upper right.
Check Unsafe mode. This will allow you to overwrite any hard drive on your computer. Be careful an uncheck when done.

Select <Back, select your OS image and select your external hard drive.
Click Flash. The USB Drive will be overwritten.

Live External HDD using Rufus

Download Rufus: https://rufus.ie/en_US/
Double click .exe file to open.
Check List USB Hard Drives.
Select Device, Boot selection, Partition scheme.
Select Persistent partition size. I usually leave a bit of space that can be shared with Windows for data.

Click START. The USB Drive will be overwritten.

edited Apr 22 '21 at 08:58

answered Apr 22 '21 at 08:28

C.S.Cameron

19,519

@Nicholas Saunders: If this provides a solution to your question, please click the check mark, upper left of this answer, to accept it. – C.S.Cameron Apr 22 '21 at 09:04
1

@Nicholasa Instructions for installing Ubuntu to the same USB the installer was booted from, can be found at: https://askubuntu.com/questions/855039/can-ubuntu-be-installed-to-the-pendrive-it-was-booted-from – C.S.Cameron Apr 22 '21 at 09:52

score 3 · Answer 2 · answered Apr 22 '21 at 08:07

Full Install vs Persistent install

Ubuntu can be installed to a USB in different ways. A Live install does not save between sessions. A Persistent install extracts the OS from a compressed file and saves data to an overlay file or partition each session, and a Full install installs the complete OS to the USB just like an install to internal disk.

Comparison between Persistent and Full install USB

Advantages of a persistent install:

You can use the persistent pendrive to install Ubuntu to another computer.
A persistent install takes up less space on the pendrive.
You can reset the pendrive by overwriting the old casper-rw file with a new one.
The install to pendrive takes less time.
Slightly less wear on the drive.

Advantages of a Full install:

You can update and upgrade.
If you have problems or wish to modify, the solution is the same as with an internal install, (You can ask for help in the forums).
No ugly startup / install screen. No time wasting disk check every boot.
Better security, you can use full encryption
You can use proprietary drivers, many drivers need to start before the Persistent overlay opens therefore they do not work with a persistent install.
Swapfiles and partitions work and Hibernation can be enabled.
Many persistent installs are limited to a 4GB casper-rw and a 4GB home-rw persistence file, to get more persistence requires persistence partitions. Once casper-rw is full, the drive will not boot.
More efficient usage of disk space. Does not require reserved space for persistence.
Faster boot, no automatic disk checking or Try Ubuntu/Install Ubuntu screen.
You can run VBox and use virtual machines.
Generally faster boot than Live or Persistent USB's.
More stable, better for day to day use. I have run Ubuntu off a flash drive for 5 years making only LTS upgrades.

Note that once booted, both methods run at about the same speed. If the computer has lots of RAM Ubuntu should run mainly in RAM and there will not be a big difference between running off internal HDD and USB3 flash drive f.

Full Install Method

A quick and easy method to flash a Full install to USB can be found here: Easy Full Install USB that Boots both BIOS and UEFI

A more traditional method for creating a Full install USB from scratch can be found here: How to Create a Full Install of Ubuntu 20.04 to USB Device Step by Step

How to make an external hard drive bootable with unetbootin?

2 Answers2

Live External HDD using balenaEtcher

Live External HDD using Rufus

Full Install vs Persistent install

Linked