Preserving evidence for a possible D-I bug report

[Richard Owlett <rowlett@cloud85.net>]

I am a atypical user.
I currently multi-boot among five instances of Jessie and Stretch.
The only OS with access to Grub is the one on sda1.

I just did a fresh install of Stretch (Debian 9.1) to sda1 using a 
purchased DVD.
I chose the non-graphical expert install.

I *MADE* a typing error.
The installer told me I had missed a step.
When asked, I chose to go back "one step".

I did. The install *APPARENTLY* proceeded normally.
*HOWEVER* I do not recall ever having been asked any questions about 
internet connectivity.

I'm currently using the Debian installed on a different partition.
Before doing anything with/to/relating to the copy of Debian on sda1, I 
wish to preserve the *MAXIMUM* amount of installation related data 
related logs.

I will access any file on sda1 via root user of install on a different 
partition.

*What files should I preserve?*

They may be no problem.
Having been "Customer Service" in another field, I prefer to "think 
first" rather than "repent at leisure".

Comments?
TIA

P.S. *NOT* using the install on sda in the short term does not cause any 
hardship.