This page will have a list of common mistakes that can be made when building a temporary network (like for a LAN-Party, a Conference et cetera)

• Consider blocking TCP/25
• Put DNS- and other important servers into a dedicated IP network in another VLAN. This will mitigate the risk of somebody unintentionally putting in the DNS Server's IP address as his local IP address and thus breaking DNS for everybody.

• Cabling
• Supplies (Crossover cables, Gender Changers)
• Wireless
• Access to Patch Rooms etc
• IP Addressing
• Internet Access
• Coordination with Security Service
  • Do not lock rooms without consultation
  • Do not switch off power

This wiki page has been inspired by my own experience as network admin, and legends and stories that I have been told numerous times in the past, most of them by people like Hanno Wagner, Jörg Hoh and Markus Wirtz.