Fix: 'Server is full' Message on an Empty Server

Players report Server is full or are dropped with a full-server message, yet the scoreboard shows open slots — sometimes the server looks completely empty. This is almost never a real capacity problem; it is a reserved-slots plugin holding slots back, a mismatch between the advertised and actual slot count, or a hung slot that is occupied by nobody. Here is how to find which, because the symptom is identical for all three.

1. Check the real maxplayers

Start from ground truth: how many slots does the server actually have? In the console:

maxplayers

This is set at startup (the -maxplayers / +maxplayers launch value) and cannot be raised without a restart. If it reads lower than you think — someone launched with maxplayers 10 — then the server genuinely is small and fills fast. If it reads a healthy number but players still get rejected on an apparently empty server, the cause is a plugin or a hidden-slot cvar below.

2. Look at reserved slots

The most common cause is a reserved-slots plugin (AMX Mod X ships adminslots.amxx). It keeps one or more slots free for admins by kicking a non-admin or refusing the connection when the server reaches capacity minus the reserved count. Its cvars:

amx_reservation 1        // number of slots reserved for admins
amx_hideslots 1          // hide the reserved slots from the public count

With amx_reservation 1, the last public slot is closed to non-admins — so a 12-slot server effectively fills at 11 for regular players, and the 12th shows Server is full to them. That is working as designed; the confusion is only if you did not know it was enabled. Lower amx_reservation to 0 if you do not want reserved slots, or explain the reservation.

3. Understand sv_visiblemaxplayers

The amx_hideslots feature works by lowering the advertised slot count so the reserved slots are invisible in the browser. That is done through sv_visiblemaxplayers:

sv_visiblemaxplayers 11

If this is set below your real maxplayers, the server browser shows fewer slots than exist — a 12-slot server advertising 11. Combined with a reservation this is intentional; set by accident, it makes the server look full or smaller than it is. Set sv_visiblemaxplayers to -1 to advertise the true count, or match it to your intended public capacity.

4. Clear a hung / ghost slot

Occasionally a slot is occupied by a connection that never fully joined or never cleaned up — a client that crashed mid-connect, a bot slot not released. The server counts it as occupied even though no player is visible. List who the engine thinks is connected:

status

Compare the player count in status against the scoreboard. If status shows connections with no name or a stuck connecting state consuming slots, that is your phantom capacity. A map change usually clears them; if a specific slot stays wedged, restart the server. Bots also occupy real slots — a bot-filler plugin set to keep the server "full" will do exactly that and reject humans once its quota fills.

5. Rule out a bot filler

Plugins that add bots to make a server look populated consume real player slots. If such a plugin fills to maxplayers, humans get Server is full even though the "players" are bots. Check its quota cvar and ensure it leaves headroom, or that it kicks a bot when a human connects. This is the one case where an "empty"-looking server (only bots, easy to overlook as empty) genuinely has no room.

Troubleshooting

• Full at maxplayers-minus-one for non-admins — reserved slots. Lower amx_reservation or accept the reservation.
• Browser shows fewer slots than real — sv_visiblemaxplayers is below maxplayers. Set it to -1 or the intended count.
• maxplayers itself is low — the server was launched small; change the launch value and restart.
• status shows stuck 'connecting' slots — ghost connections. Change map or restart to release them.
• Full but only bots inside — a bot filler took every slot. Adjust its quota to leave room for humans.
• Full message only for some players — they are non-admins hitting the reserved slot while admins get in. Expected with reservations.

Verification

Read the three numbers that matter together: maxplayers (real capacity), sv_visiblemaxplayers (advertised), and the amx_reservation value. They should describe the situation you intend — for a plain 12-slot public server with no reservation, maxplayers 12, sv_visiblemaxplayers -1, amx_reservation 0. Then have a non-admin connect to what looks like a full-but-really-open server and confirm they get in. If they connect and the counts match your intent, the phantom-full is resolved. If it recurs only at peak, it is the reserved slot doing its job — document it so it stops looking like a bug. For advertising the server correctly to the master list, confirm sv_lan 0 as covered in the essential cvars guide.