First of all, alot of us are in panic because our server members have upgraded to patch 2.3.0, and can't really use your server in practical terms, well don't despair. The first thing you need to do is go into your Logonserver.conf file and find the following block of text, and change the red text to what it is below.
################################################################################ #####
# Accepted Build Range Setup
#
# Min Build
# Minimum client build that is allowed to access the server
#
# Max Build
# Maximum client build that is allowed to access the server
#
# Latest build for Wow 2.2.0 is 7272
# Default: 7272
################################################################################ #####
<Client MinBuild = "6800"
MaxBuild = "8559"> Change to 8559!!!(or the number in bottom left corner of wow login screen, for future patches)
Now players will be able to connect even if they have the newest patch, but theres no 2.3 content on your server. unlike smaller patches where you simply have to get the new DBCs and scripts, here you have to get DBCs and Scripts, but at the same time you need to update the following tables to that of a more up-to-date database.
Creature_names
Gameobject_names
Creature_proto
Creature_loot
Gameobject_spawns
Creature_staticpawns
Gameobject_staticspawns
Gameobject Quest Pickup binding
Gameobject quest finisher
Gameobject Quest starter
Gameobject Quest item binding
Instances(if your server has this table)
ZoneGuards
items
itemloot
Reputation_******
Reputation_*******
Reputation_********
spells112
spell_(all ones with spells )
Trainers_(all ones with trainer)
etc etc etc. the best thing to do is to back up any different custom items , creatures, or quests which you have the SQLs for in a single folder, and get a new up-to-date database (none released yet... be patient). now execute back your custom data(make sure its not the whole old table).
Now Your server is 2.3.0 compatible, and functional. I would get working on the database, DBCs and scripts etc for you, but very busy with book report atm, sorry about that, this guide can also be applied to other future large patches.
this is actually pretty simple but im releasing now to save the grief of forty "how do i make server 2.30 HELPZ PLOX" threads.