Configuration settings of the build agent are stored in the <TeamCity Agent Home>/conf/buildagent.properties file.
The file can also store properties that will be published on the server as Agent properties and can participate in the Agent Requirements expressions.
All the system and environment properties defined in the file will be passed to every build run on the agent.

The file is a Java properties file.

A quick guide is:

This is an example of the file:

## The address of the TeamCity server. The same as is used to open the TeamCity web interface in the browser.
serverUrl=http://localhost:8111/

## The unique name of the agent used to identify this agent on the TeamCity server
## Use blank name to let server generate it.
## By default, this name would be created from the build agent's host name
name=Default agent

## Container directory to create default checkout directories for the build configurations.
workDir=../work

## Container directory for the temporary directories.
## Please note that the directory may be cleaned between the builds.
tempDir=../temp
 
## Container directory for agent state files and caches.
## TeamCity agent assumes ownership of the directory and can delete the content inside.
systemDir=../system

 
######################################
#   Optional Agent Properties        #
######################################
## A token which is used to identify this agent on the TeamCity server for agent authorization purposes.
## It is automatically generated and saved back on the first agent connection to the server.
authorizationToken=1234567890abcdefghijklml

Please make sure that the file is writable for the build agent process itself. For example, the file is updated to store its authorization token that is generated on the server-side.

If the "name" property is not specified, the server will generate a build agent name automatically. By default, this name will be created from the build agent's host name.

The file can be edited while the agent is running: the agent detects the change and (upon finishing a running build, if any) restarts automatically  loading the new settings. 

Optional Properties

If the default polling protocol is changed in favor of bidirectional communication between the server and the agent, the server must be able to open HTTP connections to the agent.

The port where the TeamCity build agent starts and where it listens for the incoming data from the server is determined via the ownPort property (9090 by default). If the firewall is configured, make sure that the incoming connections for this port are allowed on the agent computer.

ownPort=9090

If more than one build agent is hosted on the same machine, different ports must be assigned to them via the ownPort property in buildAgent.properties file of every agent.

 

The IP address used by TeamCity server to connect to the build agent is automatically detected by the server when the agent first connects to TeamCity, unless the ownAddress property is defined. If the machine has several network interfaces, automatic detection may fail and it is recommended to specify the ownAddress property:

ownAddress=<own IP address or server-accessible domain name>

 

Set up Agent behind Proxy

Since TeamCity 2017.1 it is possible to configure a forward proxy server for agent-to-server connections.

 


See also:

Concepts: Build Agent
Administrator's Guide: Predefined Build Parameters | Configuring Agent Requirements | Configuring Build Parameters