Overview

In "full text in multi lines" mode, a log spans multiple lines (such as a Java program log), and the line break \n cannot be used to mark the end of a log. To help CLS distinguish between logs, a first-line regular expression is used for matching. When a line of a log matches the preset regular expression, it is considered as the beginning of the log, and the log ends before the next matching line.

In "full text in multi lines" mode, a default key __CONTENT__ is also set, but the log data itself is not structured, and no log fields are extracted. The time attribute of a log is determined by the collection time.

Prerequisites

Assume the raw data of a multi-line log is:

10.20.20.10 - - [Tue Jan 22 14:24:03 CST 2019 +0800] GET /online/sample HTTP/1.1 127.0.0.1 200 628 35 http://127.0.0.1/group/1 
Mozilla/5.0 (Windows NT 10.0; WOW64; rv:64.0) Gecko/20100101 Firefox/64.0 0.310 0.310

The log is eventually structured by CLS as follows:

__CONTENT__:10.20.20.10 - - [Tue Jan 22 14:24:03 CST 2019 +0800] GET /online/sample HTTP/1.1 127.0.0.1 200 628 35 http://127.0.0.1/group/1 \nMozilla/5.0 (Windows NT 10.0; WOW64; rv:64.0) Gecko/20100101 Firefox/64.0  0.310 0.310

Directions

Logging in to the console

1. Log in to the CLS console.
2. In the left sidebar, click Log Topic to go to the log topic management page.

Creating a log topic

1. Click Create Log Topic.
2. In the pop-up, enter test-mtext as Log Topic Name and click OK.

Managing the machine group

1. After the log topic is created successfully, click its name to go to the log topic management page.
2. Click the Collection Configuration tab and click the format in which you need to collect logs.
3. On the Machine Group Management page, select the machine group to which to bind the current log topic and click Next to proceed to collection configuration.
   For more information, please see Machine Group Management.

Configuring collection

Configuring the log file collection path

On the Collection Configuration page, set Collection Path according to the log collection path format as shown below:
Log collection path format: [directory prefix expression]/**/[filename expression].

After the log collection path is entered, LogListener will match all common prefix paths that meet the [directory prefix expression] rule and listen for all log files in the directories (including subdirectories) that meet the [filename expression] rule. The parameters are as detailed below:

Common configuration modes are as follows:

• [Common directory prefix]/**/[common filename prefix]*
• [Common directory prefix]/**/*[common filename suffix]
• [Common directory prefix]/**/[common filename prefix]*[common filename suffix]
• [Common directory prefix]/**/*[common string]*

Below are examples:

Note：

• Only LogListener 2.3.9 and above support adding multiple collection paths.
• The system does not support uploading logs with contents in multiple text formats, which may cause write failures, such as key:"{"substream":XXX}".
• You are advised to configure the collection path as log/*.log and rename the old file after log rotation as log/*.log.xxxx.
• By default, a log file can only be collected by one log topic. If you want to have multiple collection configurations for the same file, please add a soft link to the source file and add it to another collection configuration.

Configuring the "full text in multi lines" mode

1. On the Collection Configuration page, select Full text in multi lines as the Extraction Mode.
2. Define a regular expression according to the following rules.
   You can choose Auto-Generate or Enter Manually to define a first-line regular expression, and the system will verify the regular expression based on the sample content.
   • Auto-Generate: enter the sample log in the text box, click Auto-Generate, and the system will automatically generate the first-line regular expression in the grayed-out text box as shown below:
   • Enter Manually: enter the sample log and first-line regular expression in the text box, click Verify, and the system will determine whether the expression has passed verification as shown below:

Configuring the collection policy

• Full collection: when LogListener collects a file, it starts reading data from the beginning of the file.
• Incremental collection: when LogListener collects a file, it starts reading data 1 MB ahead of the end of the file (for a file less than 1 MB, incremental collection is equivalent to full collection).

Configuring filter rules

Filters are designed to help you extract valuable log data by adding log collection filter rules based on your business needs. If the filter rule is a Perl regular expression, the created filter rule will be used for matching; in other words, only logs that match the regular expression will be collected and reported.

In "full text in multi lines" mode, __CONTENT__ is used as the key name of a log by default. For example, below is a sample log with full text in multi lines:

10.20.20.10 - - [Tue Jan 22 14:24:03 CST 2019 +0800] GET /online/sample HTTP/1.1 127.0.0.1 200 628 35 http://127.0.0.1/group/1 
Mozilla/5.0 (Windows NT 10.0; WOW64; rv:64.0) Gecko/20100101 Firefox/64.0 0.310 0.310

If you want to collect all logs of the machine 10.20.20.10, enter __CONTENT__ in Key and 10.20.20.10.* in Filter Rule.

Note：

The relationship logic between multiple filter rules is "AND". If multiple filter rules are configured for the same key name, previous rules will be overwritten.

Configuring indexes

1. Click Next to go to the Index Configuration page.

2. On the Index Configuration page, set the following information:

   • Index Status: select whether to enable it.
   • Full-Text Index: select whether to set it to case-sensitive.
   • Full-Text Delimiter: the default value is @&()='",;:<>[]{}/ \n\t\r and can be modified as needed.
   • Key-Value Index: disabled by default. You can configure the field type, delimiters, and whether to enable statistical analysis according to the key name as needed. To enable key-value index, you can set to .

     Note：

     Index configuration must be enabled before you can perform searches.

3. Click OK to finish collection configuration.

Related Operations

Log search

1. Log in to the CLS console.
2. On the left sidebar, click Search and Analysis to enter the search and analysis page.
3. Select the region, logset, and log topic as needed, and click Search and Analysis to search for logs according to the set query rules.