Get the Natural Selection 2.0 Dedicated Server files. This file contains the NS 2.0 Win32 and Linux Dedicated Servers.
NS 2.0 requires Half-Life Retail 220.127.116.11, CounterStrike Retail 1.5, or Day of Defeat Retail 1.0 to play.
Natural Selection v2.01 09 16 03 This is a server side patch only. Clients do not need to download it to play 2.01 unless they are hosting the game. The patch is available on both windoes and linux. This patch