The issue is that dbfilter = ^%d$ relies on the subdomain matching the database name exactly. When your domain is mydomain1.com, Odoo extracts the hostname and tries to match it against the regex pattern — but mydomain1.com does not match DatabaseA because there is no subdomain to extract.

The production-safe solution is to use %h with nginx rewriting the Host header per domain.

Step 1 — odoo.conf

dbfilter = ^%h$
list_db = False

Step 2 — nginx config for each domain

For mydomain1.com:

server {
    server_name mydomain1.com;
    location / {
        proxy_pass http://127.0.0.1:8069;
        proxy_set_header Host DatabaseA;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

For myurl2.com:

server {
    server_name myurl2.com;
    location / {
        proxy_pass http://127.0.0.1:8069;
        proxy_set_header Host DBossB;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Why this works:

proxy_set_header Host DatabaseA rewrites the Host header Odoo receives to match your database name exactly. The dbfilter ^%h$ then matches the rewritten host against your database name and connects automatically with no selector shown.

Why your current setup fails:

^%d$ extracts only the subdomain portion. On a root domain like mydomain1.com there is no subdomain — %d returns empty, the filter matches nothing, and Odoo falls back to the database creation screen.

After updating nginx:

sudo nginx -t && sudo systemctl reload nginx
sudo systemctl restart odoo

Muhammad Gharis Javed — Odoo v17/18/19 Backend Engineer