最近总结一些诊断OCeanBase的一些经验，出一个【OceanBase诊断调优】专题，也欢迎大家贡献自己的诊断OceanBase的方法。

1. 前言

obdiag定位为OceanBase敏捷诊断工具。1.2版本的obdiag支持诊断信息的一键收集，光有收集信息的能力，没有分析能力怎么行，所以我们在obdiag的1.3.0版本加上了OB集群的日志分析能力。你可以一键去分析你的集群的OB日志，看看有没有一些异常情况。

2. obdiag 日志分析设计

2.1  架构设计

主体架构还是依托于obdiag的集中式采集模式，当用户发起obdiag 的分析的时候需要去各个节点上进行采集，将采集回来的数据集中进行分析处理。

2.2 obdiag执行在线日志分析的时序图

1. 用户设置配置文件，配置文件的路径在obdiag安装目录的config/config.yml中，主要是设置所要分析的OceanBase集群的ssh登陆信息，因为obdiag需要通过ssh方式去集群拉取日志到obdiag的节点上进行分析

2. 执行obdiag analyze log <option> 命令

3. obdiag 接收到用户的analyze命令后会去解析<option> 内的参数

4. obdiag解析完analyze参数后会启动日志拉取的环节，拉取的节点是步骤一中用户配置的，拉取的日志的时间范围、过滤条件等都是步骤三<option>设定的

5. obdiag 发送远程主机的执行指令

6. 远程执行日志的grep或者cp命令来获取日志

7. 符合条件的日志会统一放到临时文件中，便于后续的回传

8. 下载远程主机上筛选出来的符合条件的日志

9. 下载完毕后，发送临时文件清理指令

10. 远程主机临时文件会被清理

11. obdiag 对远程主机拉取回来的日志文件进行分析，对于日志分析，主要规则是针对日志中的retcode进行分析，统计各retcode出现的次数、最早开始时间、最晚出现的时间以及其对应的trace_id的等信息

12. obdiag分析完日志后会在黑屏上打印出总览的日志分析信息

13. obdiag分析日志的详细信息会输出到文件中

14. 用户可以通过obdiag 输出的文件地址查看详细的日志分析报告

3. obdiag日志分析实践

obdiag analyze <analyze type> [options]

analyze type 包含如下：

• log：一键分析 OceanBase 的日志。

3.1 obdiag analyze log

使用该命令可以一键在线分析 OceanBase 集群的日志，或者通过 --files 开启离线分析模式。

• 本文所指的在线分析指的是 OceanBase 集群在线运行状态，日志分布在各个 OBServer 节点上。
• 本文所指的离线分析模式是 --files 参数传递下，可以分析已经收集到机 obdiag 部署机器上的 OBServer 节点日志。
• 需要确保已经在 obdiag 配置文件 config.yml 中配置好需要收集节点的登录信息。相关的详细配置介绍，参见 obdiag 配置。

例子：

obdiag analyze log --scope observer --from 2023-10-08 10:25:00 --to 2023-10-08 11:30:00

...
FileListInfo:
+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Node           | LogList                                                                                                                                                                                                               |
+================+=======================================================================================================================================================================================================================+
| xx.xx.xx.xx   | ['observer.log.20231008104204260', 'observer.log.20231008111305072', 'observer.log.20231008114410668', 'observer.log.wf.20231008104204260', 'observer.log.wf.20231008111305072', 'observer.log.wf.20231008114410668'] |
+----------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
...


Analyze OceanBase Online Log Summary:
+----------------+-----------+------------------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| Node           | Status    | FileName                                                                     |   ErrorCode | Message                                                                                                                       |   Count |
+================+===========+==============================================================================+=============+===============================================================================================================================+=========+
| xx.xx.xx.xx    | Completed | analyze_pack_20231008171201/xx_xx_xx_xx/observer.log.20231008104204260       |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |       2 |
+----------------+-----------+------------------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| xx.xx.xx.xx    | Completed | analyze_pack_20231008171201/xx_xx_xx_xx/observer.log.20231008111305072       |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |       8 |
+----------------+-----------+------------------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| xx.xx.xx.xx    | Completed | analyze_pack_20231008171201/xx_xx_xx_xx/observer.log.20231008114410668       |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |      10 |
+----------------+-----------+------------------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| xx.xx.xx.xx    | Completed | analyze_pack_20231008171201/xx_xx_xx_xx/observer.log.20231008114410668       |       -4009 | IO error                                                                                                                      |      20 |
+----------------+-----------+------------------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
For more details, please run cmd 'cat analyze_pack_20231008171201/result_details.txt'

快捷分析最近一段时间的日志：

在线分析最近一小时的日志，该指令执行的时候会从远程主机上拉取最近一小时的日志进行分析，诊断出出现过的错误
obdiag gather log --scope observer --since 1h


# 在线分析最近 30 分钟的日志，该指令执行的时候会从远程主机上拉取最近30分钟的日志进行分析，诊断出出现过的错误
obdiag analyze log --scope observer --since 30m

离线分析日志：

ls -lh test/
-rw-r--r--  1 admin  staff   256M Oct  8 17:24 observer.log.20231008104204260
-rw-r--r--  1 admin  staff   256M Oct  8 17:24 observer.log.20231008111305072
-rw-r--r--  1 admin  staff   256M Oct  8 17:24 observer.log.20231008114410668
-rw-r--r--  1 admin  staff    18K Oct  8 17:24 observer.log.wf.20231008104204260
-rw-r--r--  1 admin  staff    19K Oct  8 17:24 observer.log.wf.20231008111305072
-rw-r--r--  1 admin  staff    18K Oct  8 17:24 observer.log.wf.20231008114410668

obdiag analyze log --files test/

Analyze OceanBase Offline Log Summary:
+-----------+-----------+-----------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| Node      | Status    | FileName                                                              |   ErrorCode | Message                                                                                                                       |   Count |
+===========+===========+=======================================================================+=============+===============================================================================================================================+=========+
| 127.0.0.1 | Completed | analyze_pack_20231008172144/127_0_0_1_/observer.log.20231008104204260 |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |       2 |
+-----------+-----------+-----------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| 127.0.0.1 | Completed | analyze_pack_20231008172144/127_0_0_1_/observer.log.20231008111305072 |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |       8 |
+-----------+-----------+-----------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| 127.0.0.1 | Completed | analyze_pack_20231008172144/127_0_0_1_/observer.log.20231008114410668 |       -5006 | You have an error in your SQL syntax; check the manual that corresponds to your OceanBase version for the right syntax to use |      10 |
+-----------+-----------+-----------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
| 127.0.0.1 | Completed | analyze_pack_20231008172144/127_0_0_1_/observer.log.20231008114410668 |       -4009 | IO error                                                                                                                      |      20 |
+-----------+-----------+-----------------------------------------------------------------------+-------------+-------------------------------------------------------------------------------------------------------------------------------+---------+
For more details, please run cmd 'cat analyze_pack_20231008172144/result_details.txt'

4. 附录

• obdiag 下载地址： OceanBase分布式数据库-海量数据 笔笔算数
• obdiag 官方文档： OceanBase分布式数据库-海量数据 笔笔算数
• obdiag github地址： GitHub - oceanbase/oceanbase-diagnostic-tool: OceanBase Diagnostic Tool is designed to help OceanBase users quickly gather necessary information and analyze the cause of the problem.