Overview

If OceanBase Diagnostic Tool (obdiag) is independently deployed, you can use obdiag gather commands to collect diagnostic information of OceanBase Database. You can use gather scenes commands to collect the information required for troubleshooting specific issues. These commands help address the pain point in collecting information on distributed nodes.

Prerequisites

You have configured the logon information of the target nodes in the config.yml configuration file of obdiag. For more information, see Configure obdiag.

View supported scenarios

obdiag gather scene list

Use the obdiag gather scene run command

obdiag gather scene run --scene={SceneName}

The following table describes the options.

Examples

Method 1: Use the command out-of-the-box without a configuration file

obdiag gather scene run --scene={SceneName} \
    --config db_host=xx.xx.xx.xx \
    --config db_port=xxxx \
    --config tenant_sys.user=root@sys \
    --config tenant_sys.password=*** \
    --config obcluster.servers.nodes[0].ip=xx.xx.xx.1 \
    --config obcluster.servers.nodes[1].ip=xx.xx.xx.xx.2 \
    --config obcluster.servers.nodes[2].ip=xx.xx.xx.xx.3 \
    --config obcluster.servers.global.ssh_username=test \
    --config obcluster.servers.global.ssh_password=****** \
    --config obcluster.servers.global.home_path=/home/admin/oceanbase \
    --config obproxy.servers.nodes[0].ip=xx.xx.xx.3 \
    --config obproxy.servers.nodes[1].ip=xx.xx.xx.xx.4 \
    --config obproxy.servers.global.ssh_username=test \
    --config obproxy.servers.global.ssh_password=****** \
    --config obproxy.servers.global.home_path=/home/admin/obproxy

Method 2: Use the command with a configuration file

Before you use the command, make sure that you have configured the logon information of the target nodes in the config.yml configuration file of obdiag. For more information, see Configure obdiag.

obdiag gather scene run --scene={SceneName}

Tutorial for writing a task

A task is a specific scenario. obdiag runs a task based on the dedicated script file in the YAML format.

Preparations

Before you write the script file of a task, you must specify the path of the file.

The file must be stored in the directory specified by the gather.scenes_base_path parameter in the inner_config.yml configuration file in the /usr/local/oceanbase-diagnostic-tool/conf/ directory. Check whether the task falls into an existing category in the directory. If not, create a folder to declare the category.

Here is an example:

# Go to `${gather.scenes_base_path}` and create a sample file `test.yaml` for testing the observer process.
cd ~/.obdiag/gather/tasks/observer
touch test.yaml

Now you are prepared.

Write a task

To write a task is to edit the test.yaml file.

# Declare the purpose of the task.

info: "for test"

Pay attention to the details when you write the task.

Write the task

The task script is a list that declares the steps to be executed in scenario-based collection.

Why is a task a list?

• This is to ensure compatibility with different versions.

An element of a task involves the following parameters.

Here is an example:

info: testinfo
task:
  - version: "[3.1.0,3.2.4]"
    steps:
     {steps_object}
  - version: [4.2.0.0,4.3.0.0]
    steps:
     {steps_object}

steps is a list of multiple execution processes.

An element of steps is a single step that involves the following parameters.

In the following examples, step: serves only as a mark and has no actual meaning.

ssh

Remotely execute the instruction and obtain the corresponding return value.

step:
  type: ssh
  ssh: wc -l /proc/${task_OBServer_pid}/maps | awk '{print $1}'
  global: false # The `global` field specifies whether to execute a step only on a single node or on all nodes. The value `true` specifies to execute the step only on the first node. The value `false` specifies to execute the step on each node.

sql

Execute an SQL statement and obtain the corresponding value.

step:
 type: sql
 sql: select tenant_name from oceanbase. __all_tenant;
 global: false

log

Collect logs of the observer process.

step:
 type: log
 grep: "" # Fields for filtering logs.
 global: false

obproxy_log

Collect logs of OceanBase Database Proxy (ODP).

step:
 type: obproxy_log
 grep: "" # Fields for filtering logs.
 global: false

sysstat

Collect host information.

step:
 type: sysstat
 sysstat: ""
 global: false