'cstrike' and by extension de_dust2 are not shipped by Valve when installing HLDS. 'valve' represents hldm, the default hlds game/mod, and crossfire is a map that ships with that.
HLDS Servers
This is for older games like CS 1.6 (default game) and other servers that still run on the older HLDS server under id 90
ReHLDS
ReHLDS is a reverse engineered build of the original HLDS (build 6152/6153), and provides a number of fixes and improvements over the vanilla engine files, while remaining compatible with vanilla clients.
Github: https://github.com/dreamstalker/rehlds
Server Ports
HLDS servers require up to 6 ports
| Port | default |
|---|---|
| Game/rcon | 27015 |
| HLTV | 27020 |
| VAC | 26900 |