https://github.com/wikimedia/puppet/blob/production/modules/role/files/labs/db/maintain-dbusers.py now manages creating accounts for tools and Toolforge users. To stop managing the account creation for labsdb1001|3, we'll need to
- Remove labsdb1001 and 3 from the config at https://github.com/wikimedia/puppet/blob/production/modules/role/manifests/labs/db/maintain_dbusers.pp
- Clean up the metadata stores in m5-master.eqiad.wmnet (labsdbaccount.account_host), and remove entries with hostname = labsdb1001 or 1003, and status=absent - this will stop the script from attempting to create accounts in the old replica hosts for any entries with status absent
These two steps will just prevent maintain-dbusers from attempting to create new accounts in the now-readonly replicas 1001 and 1003.
After the decommission, we should clean up all the entries with hostname = labsdb1001 or 1003 in our metadata store - labsdbaccount.account_host on m5-master.