Port scan firewall with NMAP

When auditing the public-facing side of a firewall, is there an appropriate/recommended range of ports to scan? We're using NMAP. By default, an intense scan only scans the first 1000 ports. Seems pretty limited. Does anyone have a strong opinion or some professional experience regarding this? Should we scan UDP and TCP? Any example NMAP lines?

Thanks!
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meade470Asked:
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gheistCommented:
You should scan all ports if you are at it. Just make sure you disable rate-limiting and/or port scan detection for your scanning IP.
Normally you allow just few public-facing services, so nothing more should appear.
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vpnttgCommented:
TCP: nmap -sS -p 0-65535 <IP address>
UDP: nmap -sU -p 0-65535 <IP address>
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