As per the DoD Main Rules, all server addons and plugins are forbidden unless explicitly approved.
This post lists all approved addons and plugins.
Approved Server Addons:
AMX Mod XApproved
AMX Mod X Default Plugins:
admin.amxx Administration Base
admin_sql.amxx Administration Base for SQL. Use only one base.
admincmd.amxx Basic administration commands (such as kick/slap).
adminhelp.amxx Help for admin commands.
multilingual.amxx Multi-Lingual client configuration.
menufront.amxx Front-end for admin menus.
cmdmenu.amxx Command menu for settings.
plmenu.amxx Player menu commands (kick, ban, etc).
mapsmenu.amxx Maps menu (vote, changelevel, etc).
antiflood.amxx Prevents clients from flooding the say chat.
pausecfg.amxx Allows pausing/unpausing of plugins.
nextmap.amxx Displays next map in the mapcycle.
None of these may be configured or used in such a way that they display information to (or prompt, such as with a menu) any player without that player having explicitly asked for it. (Among other things, this means no voting)
Just to be clear, the following plugins should
not be running/used during any Eagle League match, despite being default AMX Mod X plugins:
adminslots.amxx Slot reservation.
telemenu.amxx Teleport Menu (fun module required).
adminchat.amxx Console-based chat commands.
scrollmsg.amxx Displays a scrolling message.
imessage.amxx Displays a centered, timed information message.
adminvote.amxx Voting commands.
mapchooser.amxx Allows players to vote for the next map.
timeleft.amxx Displays time left on the current map.
statscfg.amxx Configuration of statistical plugins.