通過上一節《微服務之分布式跟蹤系統（springboot+zipkin）》我們簡單熟悉了zipkin的使用，但是收集的數據都保存在內存中重啟後數據丟失，不過zipkin的Storage除了內存，還有Cassandra、MYSQL、ElasticSearch。

二、zipkin的各種Storage配置簡介

zipkin存在一些公用的配置，同時存在一些私有的配置（詳細信息地址為：https://github.com/openzipkin/zipkin/tree/master/zipkin-server#configuration-for-the-ui），此處不做配置說明的翻譯（因為都比較簡單易懂），其公用的配置如下所示：

1. *`QUERY_PORT`: Listen port for the http api and web ui; Defaults to 9411
2. *`QUERY_LOG_LEVEL`: Log level written to the console; Defaults to INFO
3. *`QUERY_LOOKBACK`: How many milliseconds queries can look back from endTs;Defaults to 7 days
4. *`STORAGE_TYPE`: SpanStore implementation: one of `mem`, `mysql`, `cassandra`,`elasticsearch`
5. *`COLLECTOR_PORT`: Listen port for the scribe thrift api; Defaults to 9410
6. *`COLLECTOR_SAMPLE_RATE`: Percentage of traces to retain, defaults to alwayssample (1.0).

（1）Cassandra Storage配置

1. * `CASSANDRA_KEYSPACE`: The keyspace to use. Defaults to "zipkin".
2. * `CASSANDRA_CONTACT_POINTS`: Comma separated list of hosts / ip addresses part of Cassandra cluster. Defaults to localhost
3. * `CASSANDRA_LOCAL_DC`: Name of the datacenter that will be considered "local" for latency load balancing. When unset, load-balancing is round-robin.
4. * `CASSANDRA_ENSURE_SCHEMA`: Ensuring cassandra has the latest schema. If enabled tries to execute scripts in the classpath prefixed with `cassandra-schema-cql3`. Defaults to true
5. * `CASSANDRA_USERNAME` and `CASSANDRA_PASSWORD`: Cassandra authentication. Will throw an exception on startup if authentication fails. No default
6. * `CASSANDRA_USE_SSL`: Requires `javax.net.ssl.trustStore` and `javax.net.ssl.trustStorePassword`, defaults to false.

（2）MySQL Storage配置

1. * `MYSQL_DB`: The database to use. Defaults to "zipkin".
2. * `MYSQL_USER` and `MYSQL_PASS`: MySQL authentication, which defaults to empty string.
3. * `MYSQL_HOST`: Defaults to localhost
4. * `MYSQL_TCP_PORT`: Defaults to 3306
5. * `MYSQL_MAX_CONNECTIONS`: Maximum concurrent connections, defaults to 10
6. * `MYSQL_USE_SSL`: Requires `javax.net.ssl.trustStore` and `javax.net.ssl.trustStorePassword`, defaults to false.

（3）Elasticsearch Storage配置

1. * `ES_CLUSTER`: The name of the elasticsearch cluster to connect to. Defaults to "elasticsearch".
2. * `ES_HOSTS`: A comma separated list of elasticsearch hostnodes to connect to. When in host:port
3. format, they should use the transport port, not the http port. To use http, specify
4. base urls, ex. http://host:9200. Defaults to "localhost:9300". When not using http,
5. Only one of the hosts needs to be available to fetch the remaining nodes in the
6. cluster. It is recommended to set this to all the master nodes of the cluster.
8. If the http URL is an AWS-hosted elasticsearch installation (e.g.
9. https://search-domain-xyzzy.us-west-2.es.amazonaws.com) then Zipkin will attempt to
10. use the default AWS credential provider (env variables, system properties, config
11. files, or ec2 profiles) to sign outbound requests to the cluster.
12. * `ES_PIPELINE`: Only valid when the destination is Elasticsearch 5.x. Indicates the ingest
13. pipeline used before spans are indexed. No default.
14. * `ES_MAX_REQUESTS`: Only valid when the transport is http. Sets maximum in-flight requests from
15. this process to any Elasticsearch host. Defaults to 64.
16. * `ES_AWS_DOMAIN`: The name of the AWS-hosted elasticsearch domain to use. Supercedes any set
17. `ES_HOSTS`. Triggers the same request signing behavior as with `ES_HOSTS`, but
18. requires the additional IAM permission to describe the given domain.
19. * `ES_AWS_REGION`: An optional override to the default region lookup to search for the domain
20. given in `ES_AWS_DOMAIN`. Ignored if only `ES_HOSTS` is present.
21. * `ES_INDEX`: The index prefix to use when generating daily index names. Defaults to zipkin.
22. * `ES_DATE_SEPARATOR`: The date separator to use when generating daily index names. Defaults to ‘-‘.
23. * `ES_INDEX_SHARDS`: The number of shards to split the index into. Each shard and its replicas
24. are assigned to a machine in the cluster. Increasing the number of shards
25. and machines in the cluster will improve read and write performance. Number
26. of shards cannot be changed for existing indices, but new daily indices
27. will pick up changes to the setting. Defaults to 5.

三、zipkin環境準備與啟動

在本節中，以MySQL為例進行說明，由於目前只是Mysql5.6和5.7進行測試過，所以本次我選擇Mysql5.7版本。

（1） 初始化數據庫

安裝好Mysql5.7後新建zipkin的數據庫，然後執行下面的SQL語句新建表：

1. CREATETABLE IF NOT EXISTS zipkin_spans (
2. `trace_id_high` BIGINT NOT NULL DEFAULT 0COMMENT ‘If non zero, this means the trace uses 128 bit traceIds instead of 64bit‘,
3. `trace_id` BIGINT NOT NULL,
4. `id` BIGINT NOT NULL,
5. `name` VARCHAR(255) NOT NULL,
6. `parent_id` BIGINT,
7. `debug` BIT(1),
8. `start_ts` BIGINT COMMENT ‘Span.timestamp():epoch micros used for endTs query and to implement TTL‘,
9. `duration` BIGINT COMMENT ‘Span.duration():micros used for minDuration and maxDuration query‘
10. )ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;
12. ALTERTABLE zipkin_spans ADD UNIQUE KEY(`trace_id_high`, `trace_id`, `id`) COMMENT‘ignore insert on duplicate‘;
13. ALTERTABLE zipkin_spans ADD INDEX(`trace_id_high`, `trace_id`, `id`) COMMENT ‘forjoining with zipkin_annotations‘;
14. ALTERTABLE zipkin_spans ADD INDEX(`trace_id_high`, `trace_id`) COMMENT ‘forgetTracesByIds‘;
15. ALTERTABLE zipkin_spans ADD INDEX(`name`) COMMENT ‘for getTraces and getSpanNames‘;
16. ALTERTABLE zipkin_spans ADD INDEX(`start_ts`) COMMENT ‘for getTraces ordering andrange‘;
18. CREATETABLE IF NOT EXISTS zipkin_annotations (
19. `trace_id_high` BIGINT NOT NULL DEFAULT 0COMMENT ‘If non zero, this means the trace uses 128 bit traceIds instead of 64bit‘,
20. `trace_id` BIGINT NOT NULL COMMENT ‘coincideswith zipkin_spans.trace_id‘,
21. `span_id` BIGINT NOT NULL COMMENT ‘coincideswith zipkin_spans.id‘,
22. `a_key` VARCHAR(255) NOT NULL COMMENT‘BinaryAnnotation.key or Annotation.value if type == -1‘,
23. `a_value` BLOB COMMENT‘BinaryAnnotation.value(), which must be smaller than 64KB‘,
24. `a_type` INT NOT NULL COMMENT‘BinaryAnnotation.type() or -1 if Annotation‘,
25. `a_timestamp` BIGINT COMMENT ‘Used toimplement TTL; Annotation.timestamp or zipkin_spans.timestamp‘,
26. `endpoint_ipv4` INT COMMENT ‘Null whenBinary/Annotation.endpoint is null‘,
27. `endpoint_ipv6` BINARY(16) COMMENT ‘Null whenBinary/Annotation.endpoint is null, or no IPv6 address‘,
28. `endpoint_port` SMALLINT COMMENT ‘Null whenBinary/Annotation.endpoint is null‘,
29. `endpoint_service_name` VARCHAR(255) COMMENT‘Null when Binary/Annotation.endpoint is null‘
30. )ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;
32. ALTERTABLE zipkin_annotations ADD UNIQUE KEY(`trace_id_high`, `trace_id`, `span_id`,`a_key`, `a_timestamp`) COMMENT ‘Ignore insert on duplicate‘;
33. ALTERTABLE zipkin_annotations ADD INDEX(`trace_id_high`, `trace_id`, `span_id`)COMMENT ‘for joining with zipkin_spans‘;
34. ALTERTABLE zipkin_annotations ADD INDEX(`trace_id_high`, `trace_id`) COMMENT ‘forgetTraces/ByIds‘;
35. ALTERTABLE zipkin_annotations ADD INDEX(`endpoint_service_name`) COMMENT ‘forgetTraces and getServiceNames‘;
36. ALTERTABLE zipkin_annotations ADD INDEX(`a_type`) COMMENT ‘for getTraces‘;
37. ALTERTABLE zipkin_annotations ADD INDEX(`a_key`) COMMENT ‘for getTraces‘;
38. ALTERTABLE zipkin_annotations ADD INDEX(`trace_id`, `span_id`, `a_key`) COMMENT ‘fordependencies job‘;
40. CREATETABLE IF NOT EXISTS zipkin_dependencies (
41. `day` DATE NOT NULL,
42. `parent` VARCHAR(255) NOT NULL,
43. `child` VARCHAR(255) NOT NULL,
44. `call_count` BIGINT
45. )ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;
47. ALTERTABLE zipkin_dependencies ADD UNIQUE KEY(`day`, `parent`, `child`);

（2） 啟動實例

執行命令：java -jar zipkin-server-1.17.1-exec.jar --STORAGE_TYPE=mysql--MYSQL_DB=zipkin --MYSQL_USER=root --MYSQL_PASS=root --MYSQL_HOST=localhost--MYSQL_TCP_PORT=3306，啟動成功如下圖所示：

（3） 查看運行效果

通過上圖，我們發現zipkin使用springboot，並且啟動的端口為9411，然後我們通過瀏覽器訪問，效果如下：

四、分布式跟蹤系統實踐（springboot+zipkin+mysql）

4.1場景設置與分析

現在有一個服務A調用服務B，服務B又分別調用服務C和D，整個鏈路過程的關系圖如下所示：

4.2 代碼編寫

具體代碼和上一節代碼相同，源代碼下載地址：https://github.com/dreamerkr/mircoservice.git文件夾springboot+zipkin下面。

4.3運行效果

（1）分別啟動每個服務，然後訪問服務1，瀏覽器訪問（http://localhost:8081/service1/test）

（2）輸入zipkin地址，每次trace的列表

點擊其中的trace，可以看trace的樹形結構，包括每個服務所消耗的時間：

點擊每個span可以獲取延遲信息：

同時可以查看服務之間的依賴關系：

同時查看zipkin數據庫表已經存在數據：

微服務之分布式跟蹤系統（springboot+zipkin+mysql）