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# Configuration
-We could setup enviroment variables to configure this image. Most of them is defined in [setup backends](), but Apache SkyWalking Docker Image adds extra enviroment variables to help user to compose it propertly.
+We could set up environment variables to configure this image. Most of them are defined in [backend-setup](https://github.com/apache/skywalking/blob/v6.1.0/docs/en/setup/backend/backend-setup.md), but Apache SkyWalking Docker Image adds extra environment variables to help the user to compose it properly. The details are located in [docker-entrypoint.sh](docker-entrypoint.sh)
## SW_CLUSTER
Default value is `standalone`, avaliable values are:
- - `standlone`
- - `zookeeper`
- - `kubernetes`
- - con
+
+ - `standlone`, If set this value, all enviroment variables of `cluster.standlone` in `application.yml` are avaliable.
+ - `zookeeper`, If set this value, all enviroment variables of `cluster.zookeeper` in `application.yml` are avaliable.
+ - `kubernetes`, If set this value, all enviroment variables of `cluster.kubernetes` in `application.yml` are avaliable.
+ - `consul`, If set this value, all enviroment variables of `cluster.consul` in `application.yml` are avaliable.
+
## SW_STORAGE
+Default value is `H2`, avaliable values are:
+
+ - `H2`, If set this value, all enviroment variables of `storage.h2` in `application.yml` are avaliable.
+ - `elasticsearch`, If set this value, all enviroment variables of `stroage.elasticsearch` in `application.yml` are avaliable.
+ - `mysql`, If set this value, all enviroment variables of `stroage.mysql` in `application.yml` are avaliable.
+
## XXX_ENABLED
+There are also some other configuration switchers to extend default configuration, they also have a suffix `_ENABLED`.
+
+ - `SW_RECEIVER_ZIPKIN_ENABLED` turns on/off zipkin receiver
+ - `SW_RECEIVER_JAEGER_ENABLED` turns on/off zipkin receiver
+ - `SW_EXPORTER_ENABLED` turns on/off exporter
+
# License
[Apache 2.0 License.](/LICENSE)
