Frequently Asked Questions¶

How do environment variables work?¶

All configurations in tsuru are handled through environment variables. If you need to connect with a third-party service (e.g., Twitter's API), you'll likely need extra configurations like client_id. In tsuru, you can export these as environment variables, visible only to your application's processes.

Service bindings¶

When you bind your application to a service, the service API can return environment variables for tsuru to export in your application's units. This allows seamless integration between your app and the service instance.

For example, binding to a MySQL service might automatically set: - MYSQL_HOST - MYSQL_USER - MYSQL_PASSWORD - MYSQL_DATABASE

See TSURU_SERVICES environment variable for more details on how service environment variables are structured.

How does the quota system work?¶

Quotas are handled per application and per user:

User quotas¶

Every user has a quota for the number of applications they can create. For example, with a default quota of 2 applications, attempting to create a third will result in a quota exceeded error.

Application quotas¶

Each application has a quota limiting the maximum number of units it can have. This prevents runaway scaling and helps manage cluster resources.

Managing quotas¶

Administrators can: - Set default quotas in the configuration file - Change quotas for specific users or apps using the tsuru command

# View app quota
tsuru app quota view -a myapp

# Change app quota
tsuru app quota change -a myapp 10

How does routing work?¶

tsuru has a router API interface, which makes it easy to change how routing works with any provisioner.

The default router implementation is kubernetes-router.

Multiple routers¶

Since version 0.10.0, tsuru supports multiple routers. You can:

Configure a default router in your configuration
Define custom routers per plan

This allows different applications to use different routing strategies based on their requirements.

Router configuration¶

Routers are configured in tsuru.conf:

routers:
  my-router:
    type: api
    api-url: http://router-api.example.com
    default: true