How to Set Up a 100 Tick Left 4 Dead 2 Server

A stock Left 4 Dead 2 dedicated server runs at 30 tick. To run it at 100, install the L4DToolZ extension, add -tickrate 100 to the launch line (or set sv_tickrate 100 and change map), then raise the rate cvars in server.cfg so the server actually sends and accepts 100 updates a second: sv_minrate/sv_maxrate, sv_minupdaterate/sv_maxupdaterate, sv_mincmdrate/sv_maxcmdrate, plus fps_max 0 and nb_update_frequency. For Versus, add the Boomer vomit distance fix, since vomit range shrinks above 30 tick.

Higher tick makes hit registration, melee, hunter pounces and jockey rides feel crisper, which is why competitive Versus configs use it. It also costs more CPU and bandwidth per player, so it is a choice, not a free upgrade. If you want the background first, what is tick rate in games explains it.

What you need

Step 1: Install L4DToolZ

Download the latest release from the L4DToolZ releases page, stop the server, and unzip it into left4dead2/addons. Start the server and run plugin_print in the console to confirm it loaded.

This version of L4DToolZ uses offsets instead of signatures, so game updates break it less often than the original l4dtoolz or the old tickrate_enabler, which many older guides still point to. If you have Tickrate Enabler installed from an old guide, remove it so the two do not fight.

Step 2: Set the tickrate

Two ways:

Launch option (recommended). Add it to the server's command line:

./srcds_run -game left4dead2 -port 27015 -tickrate 100 +map c1m1_hotel

Console command. L4DToolZ also adds sv_tickrate, which you can run in the console or put at the top of server.cfg:

sv_tickrate 100

It takes effect after the next map change (changelevel). This is the way to go when your host does not let you edit the launch line.

L4DToolZ updates sv_minrate and sv_minupdaterate itself when the tickrate changes, but the other rate cvars are yours to set.

Step 3: Rate cvars in server.cfg

A tickrate of 100 means nothing if the server still caps how often it sends updates to players. The L4DToolZ readme lists the cvars to adjust, noting some need the SourceMod sm_cvar prefix to get past their built in limits. A typical 100 tick block for left4dead2/cfg/server.cfg:

// 100 tick rates
sm_cvar sv_minrate 100000
sm_cvar sv_maxrate 100000
sm_cvar sv_minupdaterate 100
sm_cvar sv_maxupdaterate 100
sm_cvar sv_mincmdrate 100
sm_cvar sv_maxcmdrate 100
sm_cvar fps_max 0
sm_cvar nb_update_frequency 0.014

The readme also lists sv_client_min_interp_ratio, sv_client_max_interp_ratio, net_splitrate and net_splitpacket_maxrate as related cvars. Competitive config packs set these too. Leave them at defaults unless you are following a specific config you trust.

Restart the server, or change map, after editing server.cfg.

Step 4: Fix Boomer vomit for Versus

Above 30 tick, the Boomer's vomit reaches a shorter distance than intended, which noticeably weakens it in Versus. The L4DToolZ author split the fix into a separate SourceMod plugin, l4d2_vomit_fix. Upload the .smx to left4dead2/addons/sourcemod/plugins/ and restart. Co-op only servers can skip it, but it does no harm.

Step 5: Check it worked

In game, open the console and type:

net_graph 1

The graph shows tick and the rates you are receiving. With everything set, tick reads 100 and the update rate sits near 100 when the server is not overloaded. On the server console, stats shows the server frame rate, which should comfortably stay above the tickrate.

Step 6: Client settings

Players' own rate settings cap what they accept. For 100 tick, players add to their autoexec.cfg or type in the console:

rate 100000
cl_cmdrate 100
cl_updaterate 100

Without these, a player on default settings still receives fewer updates per second than the server can send, and gets less benefit.

How much does 100 tick cost

Running the simulation 100 times a second instead of 30 roughly triples the server's per tick work, and bandwidth per player rises with update rate. In practice:

• A 4v4 Versus server at 100 tick is light for any modern CPU core, and memory barely changes.
• Co-op with lots of common infected is heavier because of nb_update_frequency, and an 8 player co-op server at 100 tick with a big plugin list is where CPU starts to matter.
• If the server cannot hold its frame rate, players see choke and stutter in net_graph, which feels worse than a steady 60. Drop to 60 tick in that case.

The source engine runs one main thread per server, so single core speed matters more than core count. Best CPU for a game server covers why.

Common problems

On a GamezServers server

On a GamezServers Left 4 Dead 2 server, upload L4DToolZ and SourceMod with the file manager or SFTP, put sv_tickrate 100 and the rate block at the top of server.cfg, and use the live console for plugin_print and changelevel. Watch memory and CPU in the panel after a full night, and change plan if the server needs more room. For bigger co-op groups on the same extension, see how to run 8 player co-op on a Left 4 Dead 2 server.

FAQ

What tickrate does a Left 4 Dead 2 server use by default?

30 tick. Higher values need an extension such as L4DToolZ.

Is Tickrate Enabler still needed for L4D2?

No. L4DToolZ includes tickrate unlocking and is maintained to survive game updates better. Do not run both.

Do players need to change anything for 100 tick?

They should set rate 100000, cl_cmdrate 100 and cl_updaterate 100, or they will receive fewer updates than the server sends.

Does 100 tick use more server resources?

Yes, mostly CPU and bandwidth. A 4v4 Versus server handles it easily, but big co-op servers with many plugins may need to stay at 60.