# Backend存储

Skywalking存储可插拔，我们提供了以下存储解决方案，你可以通过更改'application.yml`轻松使用。

storage:
  selector: ${SW_STORAGE:elasticsearch7}

原生支持的存储

H2
ElasticSearch 6, 7
MySQL
TiDB
InfluxDB

支持存储的重分发版本。

ElasticSearch 5

# H2

要激活h2作为存储，设置存储提供者为内存中的 H2。默认的在发布的包中。请阅读[h2官方文件]（http://www.h2 database.com/html/features.html）中的Database URL Overview，你可以在Embedded, Server and Mixed 模式下将目标设置为H2。

设置如下

storage:
  selector: ${SW_STORAGE:h2}
  h2:
    driver: org.h2.jdbcx.JdbcDataSource
    url: jdbc:h2:mem:skywalking-oap-db
    user: sa

# ElasticSearch

为了激活ElasticSearch 6作为存储，将存储提供程序设置为 elasticsearch
为了激活ElasticSearch 7作为存储，将存储提供程序设置为 elasticsearch7

需要ElasticSearch 6.3.2或更高版本。HTTP RestHighLevelClient被用来连接服务器

ElasticSearch 6.3.2 ~ 7.0.0 (包含), 请下载 apache-skywalking-bin.tar.gz or apache-skywalking-bin.zip,
ElasticSearch 7.0.0 ~ 8.0.0 (包含), 请下载 apache-skywalking-bin-es7.tar.gz or apache-skywalking-bin-es7.zip.

ElasticSearch 6或7 共享相同的配置，如下所示:

storage:
  selector: ${SW_STORAGE:elasticsearch}
  elasticsearch:
    nameSpace: ${SW_NAMESPACE:""}
    clusterNodes: ${SW_STORAGE_ES_CLUSTER_NODES:localhost:9200}
    protocol: ${SW_STORAGE_ES_HTTP_PROTOCOL:"http"}
    trustStorePath: ${SW_SW_STORAGE_ES_SSL_JKS_PATH:""}
    trustStorePass: ${SW_SW_STORAGE_ES_SSL_JKS_PASS:""}
    user: ${SW_ES_USER:""}
    password: ${SW_ES_PASSWORD:""}
    secretsManagementFile: ${SW_ES_SECRETS_MANAGEMENT_FILE:""} # Secrets management file in the properties format includes the username, password, which are managed by 3rd party tool.
    dayStep: ${SW_STORAGE_DAY_STEP:1} # Represent the number of days in the one minute/hour/day index.
    indexShardsNumber: ${SW_STORAGE_ES_INDEX_SHARDS_NUMBER:2}
    indexReplicasNumber: ${SW_STORAGE_ES_INDEX_REPLICAS_NUMBER:0}
    # Batch process setting, refer to https://www.elastic.co/guide/en/elasticsearch/client/java-api/5.5/java-docs-bulk-processor.html
    bulkActions: ${SW_STORAGE_ES_BULK_ACTIONS:1000} # Execute the bulk every 1000 requests
    flushInterval: ${SW_STORAGE_ES_FLUSH_INTERVAL:10} # flush the bulk every 10 seconds whatever the number of requests
    concurrentRequests: ${SW_STORAGE_ES_CONCURRENT_REQUESTS:2} # the number of concurrent requests
    resultWindowMaxSize: ${SW_STORAGE_ES_QUERY_MAX_WINDOW_SIZE:10000}
    metadataQueryMaxSize: ${SW_STORAGE_ES_QUERY_MAX_SIZE:5000}
    segmentQueryMaxSize: ${SW_STORAGE_ES_QUERY_SEGMENT_SIZE:200}
    profileTaskQueryMaxSize: ${SW_STORAGE_ES_QUERY_PROFILE_TASK_SIZE:200}
    advanced: ${SW_STORAGE_ES_ADVANCED:""}

为了使用ElasticSearch 7，注释/删除“storage/ ElasticSearch”部分，并找到相应的配置部分(“storage/elasticsearch7”)，取消注释以启用它。

# ElasticSearch 6与Https SSL加密通信.

example:

storage:
  selector: ${SW_STORAGE:elasticsearch}
  elasticsearch:
    # nameSpace: ${SW_NAMESPACE:""}
    user: ${SW_ES_USER:""} # User needs to be set when Http Basic authentication is enabled
    password: ${SW_ES_PASSWORD:""} # Password to be set when Http Basic authentication is enabled
    clusterNodes: ${SW_STORAGE_ES_CLUSTER_NODES:localhost:443}
    trustStorePath: ${SW_SW_STORAGE_ES_SSL_JKS_PATH:"../es_keystore.jks"}
    trustStorePass: ${SW_SW_STORAGE_ES_SSL_JKS_PASS:""}
    protocol: ${SW_STORAGE_ES_HTTP_PROTOCOL:"https"}
    indexShardsNumber: ${SW_STORAGE_ES_INDEX_SHARDS_NUMBER:2}
    indexReplicasNumber: ${SW_STORAGE_ES_INDEX_REPLICAS_NUMBER:0}
    # Batch process setting, refer to https://www.elastic.co/guide/en/elasticsearch/client/java-api/5.5/java-docs-bulk-processor.html
    bulkActions: ${SW_STORAGE_ES_BULK_ACTIONS:2000} # Execute the bulk every 2000 requests
    bulkSize: ${SW_STORAGE_ES_BULK_SIZE:20} # flush the bulk every 20mb
    flushInterval: ${SW_STORAGE_ES_FLUSH_INTERVAL:10} # flush the bulk every 10 seconds whatever the number of requests
    concurrentRequests: ${SW_STORAGE_ES_CONCURRENT_REQUESTS:2} # the number of concurrent requests
    advanced: ${SW_STORAGE_ES_ADVANCED:""}

文件在' trustStorePath '被监听，一旦它被改变，ElasticSearch客户端将做重新连接.
trustStorePass 可以在运行时进行更改ElasticSearch认证的秘密管理文件.

# 每日指数时间配置

每日指数(storage/elasticsearch/dayStep, default 1) 表示索引创建期间。在此期间，将保存几天(dayStep值)的度量.

大多数情况下，用户不需要手动更改值。由于SkyWalking是为了观测大型分布式系统而设计的。但是在某些特定的情况下，用户希望设置一个很长的TTL值，比如超过60天，但是由于生产环境中的低流量，他们的ElasticSearch集群并不强大。这个值可以增加到5(或更多)，如果用户能够确保单个索引能够支持最近的指标和跟踪(本例中是5)。

例如，if dayStep == 11,

数据 [2000-01-01, 2000-01-11] 将被写入 index-20000101.
数据 [2000-01-12, 2000-01-22] 将被写入 index-20000112.

注意，TTL删除会受到这些因素的影响。你应该在TTL中增加一天的步数。例如您想要TTL == 30天和dayStep == 10，您实际上需要设置TTL = 40

# ElasticSearch认证的秘密管理文件

“secretsManagementFile”的值应该指向秘密管理文件的绝对路径。该文件以属性格式包含ElasticSearch服务器的用户名、密码和JKS密码。

user=xxx
password=yyy
trustStorePass=zzz

在应用程序中使用' user, password, trustStorePass '配置的主要区别。yaml的文件是，OAP服务器正在监视Secrets管理文件。通过第三方工具，如Vault，存储提供程序将使用新的用户名、密码和JKS密码来建立连接并关闭旧的连接。如果信息存在于文件中， “用户/密码”将被覆盖。

# 弹性搜索索引的高级配置

您可以添加“JSON”格式的高级配置，以设置“ElasticSearch索引设置”遵循ElasticSearch doc

例如, set translog settings:

storage:
  elasticsearch:
    # ......
    advanced: ${SW_STORAGE_ES_ADVANCED:"{\"index.translog.durability\":\"request\",\"index.translog.sync_interval\":\"5s\"}"}

# 建议的ElasticSearch服务器端配置

您可以添加以下配置到' elasticsearch。，根据你的环境设置值。

# In tracing scenario, consider to set more than this at least.
thread_pool.index.queue_size: 1000 # Only suitable for ElasticSearch 6
thread_pool.write.queue_size: 1000 # Suitable for ElasticSearch 6 and 7

# When you face query error at trace page, remember to check this.
index.max_result_window: 1000000

我们强烈建议您从ElasticSearch官方文档中阅读更多关于这些配置的信息。这对ElasticSearch的性能影响很大。

# ElasticSearch 6与Zipkin扩展

这个实现共享了大部分的“elasticsearch”，只是扩展到支持zipkin span存储。它有相同的配置。

storage:
  selector: ${SW_STORAGE:zipkin-elasticsearch}
  zipkin-elasticsearch:
    nameSpace: ${SW_NAMESPACE:""}
    clusterNodes: ${SW_STORAGE_ES_CLUSTER_NODES:localhost:9200}
    protocol: ${SW_STORAGE_ES_HTTP_PROTOCOL:"http"}
    user: ${SW_ES_USER:""}
    password: ${SW_ES_PASSWORD:""}
    indexShardsNumber: ${SW_STORAGE_ES_INDEX_SHARDS_NUMBER:2}
    indexReplicasNumber: ${SW_STORAGE_ES_INDEX_REPLICAS_NUMBER:0}
    # Batch process setting, refer to https://www.elastic.co/guide/en/elasticsearch/client/java-api/5.5/java-docs-bulk-processor.html
    bulkActions: ${SW_STORAGE_ES_BULK_ACTIONS:2000} # Execute the bulk every 2000 requests
    bulkSize: ${SW_STORAGE_ES_BULK_SIZE:20} # flush the bulk every 20mb
    flushInterval: ${SW_STORAGE_ES_FLUSH_INTERVAL:10} # flush the bulk every 10 seconds whatever the number of requests
    concurrentRequests: ${SW_STORAGE_ES_CONCURRENT_REQUESTS:2} # the number of concurrent requests

# ElasticSearch 6与Jaeger扩展

这个实现共享了大部分的“elasticsearch”，只是扩展到支持Jaeger存储。它有相同的配置。

storage:
  selector: ${SW_STORAGE:jaeger-elasticsearch}
  jaeger-elasticsearch:
    nameSpace: ${SW_NAMESPACE:""}
    clusterNodes: ${SW_STORAGE_ES_CLUSTER_NODES:localhost:9200}
    protocol: ${SW_STORAGE_ES_HTTP_PROTOCOL:"http"}
    user: ${SW_ES_USER:""}
    password: ${SW_ES_PASSWORD:""}
    indexShardsNumber: ${SW_STORAGE_ES_INDEX_SHARDS_NUMBER:2}
    indexReplicasNumber: ${SW_STORAGE_ES_INDEX_REPLICAS_NUMBER:0}
    # Batch process setting, refer to https://www.elastic.co/guide/en/elasticsearch/client/java-api/5.5/java-docs-bulk-processor.html
    bulkActions: ${SW_STORAGE_ES_BULK_ACTIONS:2000} # Execute the bulk every 2000 requests
    bulkSize: ${SW_STORAGE_ES_BULK_SIZE:20} # flush the bulk every 20mb
    flushInterval: ${SW_STORAGE_ES_FLUSH_INTERVAL:10} # flush the bulk every 10 seconds whatever the number of requests
    concurrentRequests: ${SW_STORAGE_ES_CONCURRENT_REQUESTS:2} # the number of concurrent requests

# 关于命名空间

当设置名称空间时，ElasticSearch中所有索引的名称将使用它作为前缀.

# MySQL

MySQL作为存储，设置存储提供程序为 mysql.

注意: MySQL驱动程序不允许出现在Apache官方发行版和源代码中。请自行下载MySQL驱动。将连接驱动程序jar复制到' oap-libs '。

storage:
  selector: ${SW_STORAGE:mysql}
  mysql:
    properties:
      jdbcUrl: ${SW_JDBC_URL:"jdbc:mysql://localhost:3306/swtest"}
      dataSource.user: ${SW_DATA_SOURCE_USER:root}
      dataSource.password: ${SW_DATA_SOURCE_PASSWORD:root@1234}
      dataSource.cachePrepStmts: ${SW_DATA_SOURCE_CACHE_PREP_STMTS:true}
      dataSource.prepStmtCacheSize: ${SW_DATA_SOURCE_PREP_STMT_CACHE_SQL_SIZE:250}
      dataSource.prepStmtCacheSqlLimit: ${SW_DATA_SOURCE_PREP_STMT_CACHE_SQL_LIMIT:2048}
      dataSource.useServerPrepStmts: ${SW_DATA_SOURCE_USE_SERVER_PREP_STMTS:true}
    metadataQueryMaxSize: ${SW_STORAGE_MYSQL_QUERY_MAX_SIZE:5000}

所有连接相关的设置，包括链接url，用户名和密码都在' application.yml '中。其他一些设置，请按照HikariCP连接池文档进行所有设置。

# TiDB

目前测试的TiDB版本为2.0.9,Mysql客户端驱动程序为8.0.13。 TiDB作为存储，设置存储提供程序为mysql。

storage:
  selector: ${SW_STORAGE:mysql}
  mysql:
    properties:
      jdbcUrl: ${SW_JDBC_URL:"jdbc:mysql://localhost:3306/swtest"}
      dataSource.user: ${SW_DATA_SOURCE_USER:root}
      dataSource.password: ${SW_DATA_SOURCE_PASSWORD:root@1234}
      dataSource.cachePrepStmts: ${SW_DATA_SOURCE_CACHE_PREP_STMTS:true}
      dataSource.prepStmtCacheSize: ${SW_DATA_SOURCE_PREP_STMT_CACHE_SQL_SIZE:250}
      dataSource.prepStmtCacheSqlLimit: ${SW_DATA_SOURCE_PREP_STMT_CACHE_SQL_LIMIT:2048}
      dataSource.useServerPrepStmts: ${SW_DATA_SOURCE_USE_SERVER_PREP_STMTS:true}
    metadataQueryMaxSize: ${SW_STORAGE_MYSQL_QUERY_MAX_SIZE:5000}

所有连接相关的设置，包括链接url，用户名和密码都在' application.yml '中。这些设置可以参考上面的MySQL配置。

# InfluxDB

流感数据库存储提供了一个时间序列数据库作为新的存储选项。

storage:
  selector: ${SW_STORAGE:influxdb}
  influxdb:
    url: ${SW_STORAGE_INFLUXDB_URL:http://localhost:8086}
    user: ${SW_STORAGE_INFLUXDB_USER:root}
    password: ${SW_STORAGE_INFLUXDB_PASSWORD:}
    database: ${SW_STORAGE_INFLUXDB_DATABASE:skywalking}
    actions: ${SW_STORAGE_INFLUXDB_ACTIONS:1000} # the number of actions to collect
    duration: ${SW_STORAGE_INFLUXDB_DURATION:1000} # the time to wait at most (milliseconds)
    fetchTaskLogMaxSize: ${SW_STORAGE_INFLUXDB_FETCH_TASK_LOG_MAX_SIZE:5000} # the max number of fetch task log in a request

所有连接相关的设置，包括链接url，用户名和密码都在' application.yml '中。元数据存储提供程序的设置可以参考上面的H2/MySQL的配置。

# ElasticSearch 5

ElasticSearch 5 和ElasticSearch 6的java客户端版本不兼容, 所有它不在原生发布中。. OpenSkywalking/SkyWalking-With-Es5x-Storage 包括这个发布版本。

# 更多存储解决方案扩展

参考开发者指南Project Extensions document中的Storage extension development guide