I booted the current jammy daily/RC (what we’ll soon release as Lubuntu 22.04.2 LTS) on a nearby box; I used thumb-drive, but what I do is the same regardless of media in use (ie. I’d do the same if using DVD or optical media; I just need to wait longer) and wait to see the scan complete in systemd journals (ie. journalctl)
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/e/efibootmgr/efibootmgr_17-1ubuntu2_amd64.deb..../pool/main/e/efibootmgr/efi>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2/grub-efi_2.06-2ubuntu7.1_amd64.deb..../pool/main/g/grub2/grub-efi_2.>
Feb 21 23:05:00 lubuntu systemd[1]: systemd-hostnamed.service: Deactivated successfully.
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2/grub-efi-ia32_2.06-2ubuntu7.1_amd64.deb..../pool/main/g/grub2/grub-e>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2/grub-efi-ia32-bin_2.06-2ubuntu7.1_amd64.deb..../pool/main/g/grub2/gr>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2-unsigned/grub-efi-amd64_2.06-2ubuntu14.1_amd64.deb..../pool/main/g/g>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2-unsigned/grub-efi-amd64-bin_2.06-2ubuntu14.1_amd64.deb..../pool/main>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/g/grub2-signed/grub-efi-amd64-signed_1.187.3~22.04.1+2.06-2ubuntu14.1_amd64.>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/m/make-dfsg/make_4.3-4.1build1_amd64.deb..../pool/main/m/make-dfsg/make_4.3->
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/s/setserial/setserial_2.17-53build2_amd64.deb..../pool/main/s/setserial/sets>
Feb 21 23:05:00 lubuntu casper-md5check[2157]: Checking ./pool/main/s/shim-signed/shim-signed_1.51.3+15.7-0ubuntu1_amd64.deb..../pool/main/s/shi>
Feb 21 23:05:06 lubuntu dbus-daemon[1452]: [system] Failed to activate service 'org.bluez': timed out (service_start_timeout=25000ms)
Feb 21 23:05:06 lubuntu pulseaudio[1836]: GetManagedObjects() failed: org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible caus>
Feb 21 23:05:26 lubuntu systemd[1]: systemd-timedated.service: Deactivated successfully.
Feb 21 23:07:15 lubuntu sudo[2189]: lubuntu : TTY=pts/0 ; PWD=/home/lubuntu ; USER=root ; COMMAND=/usr/bin/dmesg
Feb 21 23:07:15 lubuntu sudo[2189]: pam_unix(sudo:session): session opened for user root(uid=0) by (uid=999)
Feb 21 23:07:15 lubuntu sudo[2189]: pam_unix(sudo:session): session closed for user root
Feb 21 23:07:50 lubuntu casper-md5check[2157]: Checking ./casper/filesystem.squashfs............................................................>
Feb 21 23:07:50 lubuntu casper-md5check[2157]: Checking ./casper/filesystem.squashfs.gpg..../casper/filesystem.squashfs.gpg: OK
Feb 21 23:07:50 lubuntu casper-md5check[2157]: Checking ./casper/filesystem.size..../casper/filesystem.size: OK
Feb 21 23:07:50 lubuntu casper-md5check[2157]: Checking ./casper/filesystem.manifest..../casper/filesystem.manifest: OK
Feb 21 23:07:50 lubuntu casper-md5check[2157]: Checking ./casper/filesystem.manifest-remove..../casper/filesystem.manifest-remove: OK
Feb 21 23:07:51 lubuntu casper-md5check[2157]: Checking ./casper/vmlinuz...../casper/vmlinuz: OK
Feb 21 23:07:55 lubuntu sudo[2195]: lubuntu : TTY=pts/0 ; PWD=/home/lubuntu ; USER=root ; COMMAND=/usr/bin/dmesg
Feb 21 23:07:55 lubuntu sudo[2195]: pam_unix(sudo:session): session opened for user root(uid=0) by (uid=999)
Feb 21 23:07:55 lubuntu sudo[2195]: pam_unix(sudo:session): session closed for user root
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Checking ./casper/initrd......../casper/initrd: OK
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Checking ./boot/memtest86+.bin..../boot/memtest86+.bin: OK
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Checking ./boot/grub/grub.cfg..../boot/grub/grub.cfg: OK
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Checking ./boot/grub/loopback.cfg...../boot/grub/loopback.cfg: OK
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Check finished: no errors found.
Feb 21 23:08:00 lubuntu systemd[1]: Finished casper-md5check Verify Live ISO checksums.
Feb 21 23:08:00 lubuntu systemd[1]: Startup finished in 22.076s (firmware) + 18.610s (loader) + 24.369s (kernel) + 3min 49.323s (userspace) = 4m>
Feb 21 23:08:01 lubuntu sudo[2199]: lubuntu : TTY=pts/0 ; PWD=/home/lubuntu ; USER=root ; COMMAND=/usr/bin/journalctl
ie. what I look for is the following line
Feb 21 23:08:00 lubuntu casper-md5check[2157]: Check finished: no errors found.
as that tells me the media check (you should be able to see that in the logs I pasted as I included quite a bit of it for this purpose in my paste) completed successfully, and it’s this media check that is ultra-slow & can cause issues on very old/slow boxes using optical media (some cloud environments too though that had been resolved as I understand it).
With some releases the media check was visible prior to the desktop being shown (you’d see it and had the chance to ^C and skip it if fast enough) but that was changed to a background task meaning the desktop can be shown even though its still running in the background. I’m ensuring I’ve waited for that to complete prior to my installation.
FYI: I do that even when using thumb-drive or faster flash media too, as I consider it another cheap insurance (like ISO validation) to ensure my installed system is perfect. I don’t consider flash media as ultra reliable either (it can fail whenever written to) but its still pretty good for a cheap consumable product.