19.10 live image has persistence enabled by default

[Olivier Robert]

I'm not sure it's the correct place to report this...

When I boot from the 19.10 live image on a USB stick (at least my USB stick, on my computer), the live system creates and formats an additional partition on my stick, labeled "casper-rw" that's mounted read-write on /var/crash and /var/log.

Passing the "nopersistent" parameter prevents that behaviour. I tried on a specially crafted disk image on qemu comprising the unmodified live image, followed by 1 GiB of zeroes, to simulate a USB stick with some remaining space.

I didn't have that problem with the 19.04 live image, on the exact same hardware.

Could it be that the system now interprets my USB stick as non-removable media, hence assuming persistence as the default, or is everyone else affected ?

Defaulting to persistence poses problems :
- integrity checks on the USB stick fail, since it the partition table has been modified
- Despite passing the "toram" parameter, the USB stick can't be ejected without performing additional operations

ProblemType: Bug
DistroRelease: Ubuntu 19.10
Package: casper (not installed)
ProcVersionSignature: Ubuntu 5.3.0-19.20-generic 5.3.1
Uname: Linux 5.3.0-19-generic x86_64
ApportVersion: 2.20.11-0ubuntu8.2
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Wed Nov 13 03:38:19 2019
InstallationDate: Installed on 2019-09-22 (51 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
SourcePackage: casper
UpgradeStatus: Upgraded to eoan on 2019-11-01 (11 days ago)

[Michael Hudson-Doyle (mwhudson)]

This is deliberate: logs are persisted to the install media by default. As you noticed you can disable this with "nopersistent". I've just fixed the toram/todisk thing, see https://bugs.launchpad.net/ubuntu/+source/casper/+bug/1851123.