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Server.json

Learn about the server.json file that contains critical configuration data for your servers.
Read time 2 minutesLast updated 3 days ago
The 
server.json
file is a file that has variable data, such as the current allocation ID, for each server. It’s automatically generated and populated for each server based on the configuration variables and the server data. It has all the built-in configuration variables and any custom values from your build configuration variables. The 
server.json
file exists within each server’s server ID directory. By default, it has all the built-in configuration variables, such as the allocation ID supplied by your matchmaker, and the connection port. But you can also add any number of configuration variables to track in the build configuration settings. Here’s an example of what a 
server.json
file might look like when populated with the configuration variables from a server: 
{	"ipv6": "::1",	"port": "9000",	"allocatedUUID": "1a04a1ac-a31a-11ed-a5e3-00155d4f1a62",	"serverID": "12345",	"machineID": "6789",	"fleetID": "c0a3e2a1-6955-415c-b1d4-af9199833e6a",	"regionID": "f15a6c27-de2a-4848-abc3-9579fbfd2259",	"regionName": "North America",	"queryPort": "9010",	"ip": "127.0.0.1",	"queryType": "sqp",	"serverLogDir": "/mnt/unity/logs/"}

allocatedUUID

The 
allocatedUUID
variable is a special built-in configuration variable that changes each time a server is allocated or unallocated. When a server is allocated, the 
allocatedUUID
field has the server’s allocation ID. When a server is unallocated, the 
allocatedUUID
field has an empty string. Here’s an example of a 
server.json
file of an allocated server: 
{	"ipv6": "::1",	"port": "9000",	"allocatedUUID": "1a04a1ac-a31a-11ed-a5e3-00155d4f1a62",	"serverID": "12345",	"machineID": "6789",	"fleetID": "c0a3e2a1-6955-415c-b1d4-af9199833e6a",	"regionID": "f15a6c27-de2a-4848-abc3-9579fbfd2259",	"regionName": "North America",	"queryPort": "9010",	"ip": "127.0.0.1",	"queryType": "sqp",	"serverLogDir": "/mnt/unity/logs/"}
Here’s an example of a 
server.json
file of an unallocated server: 
{	"ipv6": "::1",	"port": "9000",	"allocatedUUID": "",	"serverID": "12345",	"machineID": "6789",	"fleetID": "c0a3e2a1-6955-415c-b1d4-af9199833e6a",	"regionID": "f15a6c27-de2a-4848-abc3-9579fbfd2259",	"regionName": "North America",	"queryPort": "9010",	"ip": "127.0.0.1",	"queryType": "sqp",	"serverLogDir": "/mnt/unity/logs/"}
You can track the allocation ID of a server by monitoring the 
server.json
for changes. To detect changes, set up an event trigger that detects file changes or a process to check the file for changes at a regular interval.

File location

The 
server.json
file is available on disk in the following location:
  • For Linux, it's in the 
    $HOME
    environment variable. For example 
    $HOME/server.json
    .