Questions
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How Do I Write an "Or" Logical Operator on Prometheus or Grafana
In Prometheus and Grafana, you can implement an "OR" logical operation using the or operator in Prometheus Query Language (PromQL) or by structuring queries appropriately in Grafana. Here’s how to ...
Prometheus - Convert Cpu_user_seconds to Cpu Usage %?
To convert cpu_user_seconds (or a similar metric that represents CPU time) to CPU usage percentage in Prometheus, you need to calculate the rate of CPU usage over a defined period and then normaliz...
Increasing Prometheus Storage Retention
Increasing the storage retention period for Prometheus allows you to keep your metrics data for a longer duration, which can be essential for historical analysis, debugging, and reporting. Here's h...
How Can I Group Labels in a Prometheus Query?
Grouping labels in a Prometheus query allows you to aggregate metrics based on specific labels, providing a way to analyze data across different dimensions. You can use the by clause in Prometheus ...
How Can I 'Join' Two Metrics in a Prometheus Query?
Joining two metrics in Prometheus is commonly achieved through the use of the * operator or the group function, allowing you to perform operations between metrics based on their labels. Unlike trad...
How to Calculate Containers' Cpu Usage in Kubernetes With Prometheus as Monitoring?
To calculate CPU usage for containers in a Kubernetes cluster using Prometheus, you need to set up Prometheus to scrape metrics from your Kubernetes nodes and pods. Here’s a step-by-step guide on h...
Prometheus Query to Count Unique Label Values
To count unique label values in Prometheus, you can use the count function along with the by clause to aggregate metrics based on a specific label. This is useful when you want to find out how many...
Prometheus - Add Target Specific Label in Static_configs
Adding target-specific labels in the static_configs section of your Prometheus configuration file (prometheus.yml) allows you to associate additional metadata with your targets. This can be useful ...
How Do I Write a Prometheus Query That Returns the Value of a Label?
To write a Prometheus query that returns the value of a specific label, you need to use the basic syntax for querying metrics and utilize the appropriate label matchers. Here’s how to construct a q...
How to Persist Data in Prometheus Running in a Docker Container?
Persisting data in Prometheus while running it in a Docker container is crucial to ensure that your metrics data is not lost when the container is stopped or removed. Here’s a step-by-step guide on...
Usecases: Influxdb Vs. Prometheus
When choosing between InfluxDB and Prometheus, it's essential to consider their distinct features and use cases. Both databases are designed for time-series data, but they have different strengths ...
Get Total Requests in a Period of Time
To calculate the total number of requests over a specified period of time using Prometheus, you can utilize the increase function. This function is ideal for summing up the total count of a counter...
Do I Understand Prometheus's Rate Vs Increase Functions Correctly?
Understanding the rate and increase functions in Prometheus is crucial for accurately analyzing time-series data. Here's a detailed breakdown of both functions and their differences to ensure you h...
How to Stop Logstash From Creating a Default Mapping in Elasticsearch
When Logstash sends data to Elasticsearch, it can automatically create indices and mappings for new data types. However, this can lead to issues, especially if the default mapping doesn’t fit your ...
Logstash - Remove Deep Field From Json File
To remove a deep field from a JSON document in Logstash, you can use the mutate filter, specifically the remove_field directive. This allows you to specify the exact field path you want to remove f...
Check if a String Starts With Number Using Regular Expression
To check if a string starts with a number using a regular expression (regex), you can use a pattern that matches the beginning of the string (^) followed by any digit (\\d). Here’s how you can do t...
Get the Number of Fields on an Index
To get the number of fields in an index created by Logstash in Elasticsearch, you can use Elasticsearch's RESTful API to retrieve the index mapping. The mapping contains information about the field...
Regex Query Syntax Examples in Kibana
Using regular expressions (regex) in Kibana can enhance your ability to query and filter logs and data effectively. Kibana supports regex in its query DSL, particularly in the query_string and wild...
Send Spring Boot Logs Directly to Logstash With No File
Sending Spring Boot logs directly to Logstash without writing them to a file can be achieved using a logging library like Logback or Log4j2 configured to send logs over a network protocol such as T...
Logstash Configtest
Testing your Logstash configuration is an essential step to ensure that your pipelines are correctly set up and functioning as expected. Logstash provides a built-in command-line option to test the...
Is It Possible to Have Centralised Logging for Elasticbeanstalk Docker Apps?
Yes, it is possible to implement centralized logging for Docker applications running on AWS Elastic Beanstalk. Centralized logging helps in monitoring and troubleshooting by aggregating logs from m...
Docker Apps Logging With Filebeat and Logstash
Logging Docker applications using Filebeat and Logstash is a robust solution for collecting, processing, and storing log data. This setup helps in centralizing logs and analyzing them effectively. ...
How to Create Multiple Indexes in Logstash.conf File?
Creating multiple indexes in a Logstash configuration file allows you to organize your data efficiently based on different criteria or log sources. This can be achieved by defining multiple output ...
Import Csv Into Elasticsearch
Importing CSV files into Elasticsearch can be accomplished through several methods, including using Logstash, the Elasticsearch Bulk API, or tools like Kibana. Below, I’ll detail how to do this usi...
List of Syntax for Logstash's Grok
Logstash's Grok filter provides predefined patterns for parsing logs and extracting fields. Here’s a guide to common Grok syntax patterns and examples for their usage. Common Grok Patterns Data Typ...
Can I Delete the Message Field From Logstash?
Yes, you can delete the message field in Logstash if it’s no longer needed after processing. This can be useful for reducing data volume in Elasticsearch or removing redundant information. Here’s a...
Logstash Date Filter Not Updating @Timestamp With Apache Timestamp
If your Logstash date filter isn’t updating the @timestamp field using an Apache log timestamp, it’s often due to mismatches in date format or incorrect field mapping. Here’s a guide to troubleshoo...
How to Debug the Logstash File Plugin
The Logstash file plugin is commonly used to ingest log files, but issues can arise with log reading, file monitoring, or sincedb persistence. Here’s a quick guide to debugging the file plugin effe...
Searchphaseexecutionexception[failed to Execute Phase [Query], All Shards Failed]
The SearchPhaseExecutionException[failed to execute phase [query], all shards failed] error in Elasticsearch usually indicates that a query failed to execute on one or more shards in your cluster. ...
Logstash Date Parsing as Timestamp Using the Date Filter
In Logstash, you can use the date filter to parse dates from log messages and set them as the @timestamp field in your events. This is useful when the timestamp in your logs doesn’t match Logstash'...
Logstash Grok Multiline Message
To process and parse multiline messages with Logstash and the Grok filter, you need to: Combine the multiline logs into a single event using the multiline codec. Use the grok filter to extract fiel...
How to Process Multiline Log Entry With Logstash Filter?
To process multiline log entries in Logstash, you can use the codec option within the file input plugin to treat multiline messages as a single event. Here’s how: Example Configuration Set up the m...
Logstash: How to Add File Name as a Field?
To add the file name as a field in Logstash, you can use the path metadata provided by the file input plugin. Here’s a basic configuration: Use the file input plugin: Capture the path value (the fi...
How to Correctly Parse Text File Using Rsyslog and Imfile
To correctly parse a text file using rsyslog and the imfile module, you need to configure rsyslog to read and process the log file according to your needs. Here's a step-by-step guide on how to set...
Rsyslog to Direct Log Messages to Local Syslog Host on Port 5000 Using Tcp
To configure rsyslog to direct log messages to a local syslog host on port 5000 using TCP, you will need to modify the rsyslog configuration files. Here’s a step-by-step guide to set this up: 1. Co...
What Order Does Rsyslog Process Configuration Files in /Etc/rsyslog.d?
rsyslog processes configuration files in the /etc/rsyslog.d/ directory in lexicographical order. This means that files are processed in the order of their filenames, which is typically alphabetical...
Rsyslog Inside Docker Containers => "Rsyslogd Is Not Running ... Failed"
When you encounter an issue where rsyslogd is not running inside a Docker container, it could be due to a variety of reasons, including misconfiguration, missing dependencies, or improper initializ...
HAProxy Not Logging With Rsyslog
If HAProxy is not logging with rsyslog, it typically means that HAProxy logs are either not being generated or are not being forwarded correctly to rsyslog. Here’s a comprehensive guide to troubles...
Why Can't Rsyslogd Find Libgcc_s.so.1?
If rsyslogd cannot find libgcc_s.so.1, it typically indicates an issue with the system's dynamic linker not being able to locate this shared library. libgcc_s.so.1 is part of the GCC (GNU Compiler ...
Increase Precision of Apache Log to Include Milliseconds
To increase the precision of Apache logs to include milliseconds, you need to customize the log format in Apache's configuration. Apache's default logging format does not include milliseconds, but ...
Rsyslog Conditional Repeatedmsgreduction
rsyslog's repeatedmsgreduction feature is designed to reduce the verbosity of logs by suppressing repeated messages that occur within a specified time interval. This is particularly useful for mana...
Config Rsyslog With Rails Elastic Beanstalk
To configure rsyslog with a Rails application running on AWS Elastic Beanstalk, you'll need to set up log forwarding so that logs generated by your Rails application are sent to a centralized syslo...
Logstash Vs Rsyslog for Log File Aggregation
When considering log file aggregation, both Logstash and rsyslog are powerful tools, but they serve slightly different purposes and have different strengths. Here's a comparative overview to help y...
Writing Log Data to Syslog Using Log4j
To write log data to syslog using Log4j, you need to configure Log4j to send log messages to a syslog server. Log4j supports syslog through appenders, which are components responsible for sending l...
Centralized Rsyslog : Max Size of Message
In a centralized rsyslog setup, managing the maximum size of log messages is important to ensure that large messages do not cause issues with performance or storage. rsyslog has configuration optio...
How Can I Find Messages in Graylog Based on Level (Syslog Severity/priority)
To find messages in Graylog based on their level (syslog severity/priority), you'll need to use Graylog's search and filter capabilities. Graylog indexes log messages, and you can query and filter ...
How Can I Log From Python to Syslog With Either Sysloghandler or Syslog on Mac Os X And Debian (7)
Logging from Python to syslog on both macOS and Debian can be done using the SysLogHandler class from the logging module, which is available in the Python standard library. This handler sends log m...
How to Configure Syslog so That an Applications Log Goes to a Specific File
To configure syslog so that a specific application’s logs go to a particular file, you need to set up filtering and routing rules in your rsyslog configuration. Here’s a step-by-step guide on how t...
How to Make Systemd Kill or Stop Respawning the Rsyslog Daemon
To prevent systemd from respawning or automatically restarting the rsyslog daemon, you need to modify the service configuration. Here’s how you can do that: 1. Modify rsyslog Service Configuration ...
Rsyslogd and Characters #012 and #015
In the context of rsyslogd, #012 and #015 are hexadecimal representations of ASCII control characters: #012: This represents the Line Feed (LF) character, often denoted as \\n in many programming l...
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