Dan Norton composed on 2017-11-13 18:04 (UTC-0500):
Felix Miata wrote:
There's no need for separate home file systems to keep one installation from
causing corruption to another's user settings. Simply do not reuse UIDs[1].
On your first, your Jessie probably has a user dan with UID 1000. On the next,
don't use 1000 for user dan. Pick any other number, e.g. 1200 for user dan in
Stretch. During Stretch installation make the initial user dan8 or dan01 using
Jessie's UID (probably 1000) for dan.
Do you pick a UID during install somehow or do you login as root before
anything else and edit /etc/passwd?
I could have been clearer. "During installation" isn't necessarily the correct
time for user management. I don't remember whether Stretch forces ordinary user
creation at installation time, or leaves it up to the admin to do when he chooses.
With installers that force creation of an ordinary user in addition to providing
a root password, or that don't permit UID selection for an ordinary user, create
a throwaway user. On first boot after installation, login as root and use ls -n,
groupadd, useradd, userdel, etc. to delete the throwaway, and manage users as
you wish. Editing /etc/passwd should not be necessary, but is an option
available to the adventurous.