The Version Control Settings page for a build configuration allows configuring how project source code is retrieved from VCS: you can attach a VCS Root here and configure checkout options.
The VCS Checkout mode is a setting that affects how project sources reach an agent. This mode affects only sources checkout. The current revision and changes data retrieving logic is executed by the TeamCity server and thus TeamCity server needs to access the VCS server in any mode.
Depending on the version control used, agents can require command line clients installed and available in PATH on the agents (e.g. Perforce, Git, Mercurial).
The checkout mode is configured on the build configuration's Version Control Settings page, in the Checkout Options section (an advanced setting).
TeamCity has the following VCS checkout modes:
|Prefer to checkout files on agent|
This is the default setting for the newly created build configurations. When upgrading, the checkout mode settings for existing build configurations are preserved.
With this setting enabled, TeamCity will use the agent-side checkout described below if possible. If the agent-side checkout is not possible, TeamCity will display a corresponding health report item and will use the server-side checkout described below.
TeamCity falls back to the server-side checkout in the following cases:
Always checkout files on server
The TeamCity server will export the sources and pass them to an agent before each build. Since the sources are exported rather than checked out, no administrative data is stored in the agent's file system and version control operations (like check-in, label or update) cannot be performed from the agent. TeamCity optimizes communications with the VCS servers by caching the sources and retrieving from the VCS server only the necessary changes. Unless clean checkout is performed, the server sends to the agent incremental patches to update only the files changed since the last build on the agent in the given checkout directory.
Always checkout files on agent
The build agent will check out the sources before the build. Agent-side checkout frees more server resources and provides the ability to access version control-specific directories (.svn, CVS, .git); that is, the build script can perform VCS operations (e.g. check-ins into the version control) — in this case ensure the build script uses credentials necessary for the check-in.
Do not check out files automatically
TeamCity will not check out any sources automatically, the default build checkout directory will still be created so that you could use it to check out the sources via a build script. Please note that TeamCity will accurately report changes only if the checkout is performed on the revision specified by the build.vcs.number.* properties passed into the build.