This topic describes how to collect JSON logs and configure indexes. You can specify the required settings in the Log Service console.

Background information

JSON logs can be written in the following two types of structures:
  • Object: a collection of key-value pairs.
  • Array: an ordered list of values.

Logtail can parse JSON objects from logs and extract the key and value from the first layer of an object. The extracted key is used as the field name, and the extracted value is used as the field value. The valid data types of field values include object, array, and elementary data type, such as a string or a number.

Logtail cannot automatically parse JSON array from logs. You can use the full regex mode or simple mode to collect logs. For more information, see Collect logs by lineor Use the full regex mode to collect logs.

JSON logs are separated by \n. Each line contains only one log entry.

The following examples list some JSON log entries:

{"url": "POST /PutData? Category=YunOsAccountOpLog&AccessKeyId=U0Ujpek********&Date=Fri%2C%2028%20Jun%202013%2006%3A53%3A30%20GMT&Topic=raw&Signature=pD12XYLmGxKQ%2Bmkd6x7hAgQ7b1c%3D HTTP/1.1", "ip": "", "user-agent": "aliyun-sdk-java", "request": {"status": "200", "latency": "18204"}, "time": "05/May/2016:13:30:28"}
{"url": "POST /PutData? Category=YunOsAccountOpLog&AccessKeyId=U0Ujpek********&Date=Fri%2C%2028%20Jun%202013%2006%3A53%3A30%20GMT&Topic=raw&Signature=pD12XYLmGxKQ%2Bmkd6x7hAgQ7b1c%3D HTTP/1.1", "ip": "", "user-agent": "aliyun-sdk-java", "request": {"status": "200", "latency": "10204"}, "time": "05/May/2016:13:30:29"}


  1. Log on to the Log Service console.
  2. In Import Data section, select JSON - Text Log.
  3. In the Specify Logstore step, select the target project and Logstore, and click Next.
    You can also click Create Now to create a project and a Logstore. For more information, see Step 1: Create a project and a Logstore.
  4. In the Create Machine Group step, create a machine group.
    • If a machine group is available, click Using Existing Machine Groups.
    • If no machine group is available, perform the following steps. The following steps take ECS instances as an example to describe how to create a machine group:
      1. Click the ECS Instances tab. On the tab, select the ECS instances that you want to add to a machine group and then click Install.

        If Logtail is installed on the ECS instances, click Complete Installation.

        • If the ECS instances run Linux, click Install and Logtail is automatically installed on the ECS instances.
        • If the ECS instances run Windows, you must manually install Logtail on the ECS instances. For more information, see Install Logtail in Windows.
        • If you want to collect logs from a user-created cluster, you must manually install Logtail on the servers in the cluster. For more information, see Install Logtail in Linux or Install Logtail in Windows.
      2. After the installation is completed, click Complete Installation.
      3. On the page that appears, set relevant parameters for the machine group. For more information, see Create an IP address-based machine group or Create a custom ID-based machine group.
  5. In the Machine Group Settings step, apply Logtail configurations to the machine group.
    Select the created machine group and move the group from Source Machine Groups to Applied Machine Groups.
  6. In the Logtail Config step, create a Logtail configuration.
    Parameter Description
    Config Name The name of the Logtail configuration. The name cannot be modified after the Logtail configuration is created.

    You can also click Import Other Configuration to import Logtail configurations from other projects.

    Log Path The path and name of the specified log file.
    The specified log file names can be complete file names or file names that contain wildcards. For more information about wildcards that can be used in patterns of directory and file names, visit Wildcard matching. The log files in all levels of subdirectories under the specified directory that match the specified pattern are monitored. Examples:
    • /apsara/nuwa/ ... /*.log indicates the files whose extension is .log in the /apsara/nuwa directory and its subdirectories are monitored.
    • /var/logs/app_* ... /*.log* indicates each file that meets the following conditions is monitored: The file name contains .log. The file is stored in a subdirectory (at any level) of the /var/logs directory. The name of the subdirectory matches the app_* pattern.
    • A log file can be collected by using only one Logtail configuration file.
    • You can include only asterisks (*) and question marks (?) as wildcard characters in the log path.
    Blacklist If this switch is turned on, you can configure a blacklist in the Add Blacklist section. You can configure a blacklist to skip the specified directories or files during log data collection. The names of the specified directories and files support exact match and wildcard match. Examples:
    • If you select Filter by Directory from the Filter Type drop-down list and enter /tmp/mydir in the Content column, all files in the directory are skipped.
    • If you select Filter by File from the Filter Type drop-down list and enter /tmp/mydir/file in the Content column, only the specified file in the directory are skipped.
    Docker File If the file in the Docker container is a log file, you can directly specify the log path and container tags. Logtail automatically monitors the creation and destruction of containers, and collects log entries of the specified containers based on the specified tags. For more information about container text logs, see Use the console to collect Kubernetes text logs in the DaemonSet mode.
    Mode The default value is JSON Mode. You can select other modes. For more information about how to configure other modes, see Overview.
    Use System Time
    • If you turn on the Use System Time switch, the current system time of the server where Logtail is installed is used as the log time.
    • If you turn on the Use System Time switch, you must specify a key and format for the time field. For more information about how to configure the time format, see Time formats.
    Drop Failed to Parse Logs
    • If you turn on the Drop Failed to Parse Logs switch, logs that fail to be parsed cannot be uploaded to Log Service.
    • If you turn off the Drop Failed to Parse Logs switch, raw logs are uploaded when the raw logs fail to be parsed.
    Maximum Directory Monitoring Depth The maximum number of directory layers that can be recursively monitored during log collection. Valid values: 0 to 1000. The value 0 indicates that only the directory specified in the Log Path parameter is monitored.
    Specify Advanced Options based on your business requirements. We recommend that you do not modify the default settings unless otherwise required.
    Parameter Description
    Enable Plug-in Processing Specifies whether to use plug-ins for Logtail to process logs. If you turn on the switch, plug-ins are used to process logs.
    Upload Raw Log If you turn on this switch, raw logs are written to the __raw__ field and uploaded with the parsed logs.
    Topic Generation Mode
    • Null - Do not generate topic: This mode is selected by default. In this mode, the topic field is set to an empty string and you can query logs without the need to enter a topic.
    • Machine Group Topic Attributes: This mode is used to differentiate log data that is generated by different servers.
    • File Path Regex: If you select File Path Regex for Topic Generation Mode, you must configure a regular expression in the Custom RegEx field. The part of a log path that matches the regular expression is used as the topic name. This mode is used to differentiate log data that is generated by different users or ECS instances.
    Log File Encoding
    • utf8: indicates UTF-8 encoding.
    • gbk: indicates GBK encoding.
    Timezone The time zone where logs are collected.
    • System Timezone: This option is selected by default. It indicates that the time zone where logs are collected is the same as the time zone to which the server belongs.
    • Custom: Select a time zone.
    Timeout If a log file is not updated within the specified period of time, Logtail considers the file to be timed out.
    • Never: All log files are continuously monitored and never time out.
    • 30 Minute Timeout: If a log file is not updated within 30 minutes, Logtail considers the log file to be timed out and no longer monitors the file.

      If you select 30 Minute Timeout, you must set Maximum Timeout Directory Depth. Valid values: 1 to 3.

    Filter Configuration Specifies to collect logs that match the filtering conditions. Examples:
    • If you want to collect only the logs with the severity level of WARNING or ERROR, set the condition Key:level Regex:WARNING|ERROR. It indicates that logs with the severity level of WARNING or ERROR are collected.
    • Filter logs that do not meet a condition:
      • Set the condition to Key:level Regex:^(?!. *(INFO|DEBUG)). * if you want to filter out the logs with the severity level of INFO or DEBUG.
      • Set the condition to Key:url Regex:. *^(?!.*(healthcheck)). * if you want to filter out the logs whose URL contains the keyword healthcheck. For example, logs in which the value of the url key is /inner/healthcheck/jiankong.html are not collected.

    For more examples, see regex-exclude-word and regex-exclude-pattern.

  7. In the Configure Query and Analysis step, set indexes.
    Indexes are configured by default. You can reconfigure the indexes as needed. For more information, see Enable and configure the index feature for a Logstore.
    • You must set Full Text Index or Field Search. If you set both of them, the settings of Field Search prevail.
    • If the data type of an index is Long or Double, the Case Sensitive and Delimiter settings are unavailable.

After all configurations are completed, Log Service starts to collect logs.