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1. Go to ServiceNow, ideally not PROD instance, and login as admin user.
2. Navigate to application filter (top left corner), type in sys_user.list to dump the user table.
3. This will find potentially 200k or so entries, and you cannot export that many accounts.
4. Define a filter, which shows you a subset of users. Here's a way: "NetID starts with b"
5. Apply that filter, which limited me down to 7715 hits
6. Right click on the results page, along the column headers.
7. You will get a new menu, with an Export submenu
8. Pick CSV out of that list
9. Choose to download the export

How to rebuild a user_sys locally

I had a collection of .csv files with fewer than 50k entries, but it's nicer to work with the full set when performing queries.

cat users_starts_numeric.csv users_starts_with_a-c.csv users_starts_with_d-i.csv users_starts_with_j-l.csv users_starts_with_m-r.csv users_starts_with_s-z.csv > all_users.csv
# catch the header lines, and delete all but the first one
grep -n user_name all_users.csv
sed "175824d;127985d;81587d;41395d;125d" all_users.csv > all_users_one_header.csv 
cut -d, -f1 all_users_one_header.csv > all_users_just_usernames.csv

How to parse the export csv with a subset of the user table...

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