Logging
Java Logging Basics: Concepts, Tools, and Best Practices
Imagine you're a detective trying to solve a crime, but all the evidence is invisible. Sounds impossible, right? That's exactly what it's like trying to debug a Java application without
17 Linux Log Files You Must Be Monitoring
Imagine waking up to a critical system failure that has brought your business operations to a standstill. Panic sets in as you scramble to understand what went wrong. You sift
Best Logging Practices: 14 Do’s and Don’ts for Better Logging
Ever found yourself drowning in a sea of log data, struggling to make sense of the overwhelming noise? Or perhaps faced a major system breakdown, only to find that your
Log Formatting: 8 Best Practices for Better Readability
Logs act as silent sentinels, recording every whisper of your application's activity. They are invaluable chronicles illuminating system behavior, diagnosing issues, and providing crucial insights into your application's health. However, the
10 Best Grafana Alternatives [2023 Comparison]
As an observability tool, Grafana has a lot to offer. Not only can users utilize their opensource solution for decently comprehensive and scalable metrics, but they can take advantage of
10 Best Graylog Alternatives [2023 Comparison]
Graylog is unique in the fact that it offers both a cloud and open-source solution. Many people know it well from its open-source capabilities, which are often more than enough
How to Create Log-Based Metrics to Improve Application Observability
As a Site Reliability Engineer (SRE) or DevOps professional, you are well aware of the importance of observability in ensuring the smooth functioning and performance of your applications. Observing and
Uncovering Business Insights from Logs
In the world of modern business, data drives decision-making. Every interaction, every transaction, and every click generates a series of data in the form of logs. These logs, often seen
10 Best Papertrail Alternatives [2023 Comparison]
Being a part of SolarWinds, Papertrail is one of the more well-known log management tools out there. It's powerful in terms of log aggregation and management, but it doesn't always
Elasticsearch to OpenSearch Migration Facilitated by Sematext Cloud
OK, so you've decided to move from Elasticsearch to OpenSearch. Maybe our comparison helped you decide and maybe you've checked our guide on how to perform the migration. But how
Top 10+ Best Log Monitoring Tools & Software: Free & Paid [2023 Comparison]
Log monitoring tools enhance visibility by centralizing data from multiple applications and infrastructure elements, thus ensuring your organization's good health and its business performance. Companies face increasing challenges in managing
10 Best New Relic Alternatives & Competitors [2023 Comparison]
New Relic is a huge name in the website observability and analytics industry. They've carved out a space for themselves in a highly competitive monitoring space, and have garnered thousands
10 Best Splunk Alternatives [2023 Comparison]
In the website monitoring and observability space, there are few names that hold as much weight as Splunk. Established in 2003, Splunk is highly focused on log data visualization and
Java Logging Frameworks Comparison: SLF4j vs Log4j vs Logback vs Log4j2 [Differences]
Any software application or a system can have bugs and issues in testing or production environments. Therefore, logging is essential to help troubleshoot issues easily and introduce fixes on time.
Python Logging Tutorial: How-To, Basic Examples & Best Practices
Logging is the process of keeping records of activities and data of a software program. It is an important aspect of developing, debugging, and running software solutions as it helps
10 Best Apache Log Analyzers: Free & Paid Tools [2023 Comparison]
Apache is the second most popular web server, after …., with its roots and official release going back as far as 1995. Throughout the years, it gained features, including HTTP/2,
Apache Tomcat Logging Configuration: How to View and Analyze Log Files
Apache Tomcat is the Java web server that implements many Java features like web site APIs, Java server pages, Java Servlets, etc. It's an open-source software widely used in the
5 Logstash Alternatives [2023 Review]
When it comes to centralizing logs to Elasticsearch, the first log shipper that comes to mind is Logstash. People hear about it even if it’s not clear what it does:
20+ Best Log Management Tools for Monitoring, Analytics & More: Pros & Cons Comparison [2023]
Whether you capture them for application security and compliance, production monitoring, performance monitoring, or troubleshooting, logs contain valuable information about the health of your apps. But it all comes down
Best Java GC Log Analyzers: Top Analysis Tools You Need to Know in 2023
When an application written for the Java Virtual Machine is running, it constantly creates new objects and puts them on the heap. Well, at least in the vast majority of
15 Best Log Analysis Tools & Log Analyzers of 2024 (Paid, Free & Open-source)
Log analysis and management tools have become essential in troubleshooting. With logging analysis tools – also known as network log analysis tools – you can extract meaningful data from logs
9 Best Cloud Logging Services for Log Management, Analysis, Monitoring & More [2023 Comparison]
Log management stopped being a very simple operation quite some time ago. Long gone are the "good old days" when you could log into the machine, check the logs, and
Top 7 NGINX Log Analyzer Tools [2024 Comparison]
NGINX is a highly popular web server considered one of the fastest solutions on the market. You can use it for serving data for small, personal projects, as a reverse
Ubuntu Logs: How to Check and Configure Log Files
Ubuntu provides extensive logging capabilities, so most of the activities happening in the system are tracked via logs. Ubuntu logs are valuable sources of information about the state of your
HAProxy Logging Configuration Explained: How to Enable and View Log Files
HAProxy is generally the frontend layer of your application, which means it plays a critical role since all traffic first lands on this layer. Because of this, you need to
How to Tail Kubernetes Logs: Using the Kubectl Command to See Pod, Container, and Deployment Logs
Logs are a critical aspect of any production workload, as they give you insight into what is happening in your system and tell you which components may be having issues.
Black Friday log management (with the Elastic Stack) checklist
For this Black Friday, Sematext wishes you: more products sold more traffic and exposure more logs :) Now seriously, applications tend to generate a lot more logs on Black Friday,
PostgreSQL Logs Explained: Logging Configuration Tutorial
PostgreSQL is an open-source relational database management system that's been utilized in continuous development and production for 30 years now. Nearly all the big tech companies use PostgreSQL, as it
Beginner’s Guide to RabbitMQ Logging: How to View, Locate, and Analyze Logs
RabbitMQ is one of the most popular open-source message brokers available. Its ability to be deployed in various configurations and on various platforms makes it a widely used tool; it
NGINX Error & Access Logs: Tutorial for How to View and Configure Them for Efficient Logging
NGINX is one of the most widely used reverse proxy servers, web servers, and load balancers. It has capabilities like TLS offloading, can do health checks for backends, and offers
What Is Log Aggregation: A Complete Guide to Best Practices & Tools You Need to Know
Every developer's worst nightmare is digging through a huge log file, trying to pinpoint problems. The troubleshooting most likely won't stop there. They'll have to follow the trail to multiple
How to Handle Java Lang OutOfMemoryError Exceptions
All the applications that you're trying to execute require memory. It doesn't matter if the application was developed using assembly language. Or if you used a low-level programming language like
Log4Shell: How We Protect Sematext Users
On December 9, 2021, a vulnerability was reported that could allow a system running Apache Log4j 2 version 2.14.1 or below to be compromised and allow an attacker to execute
Understanding Apache Logging: How to View, Locate and Analyze Access & Error Logs
Apache - the technology that powers the web. I'm not sure if that is correct, but I think that we wouldn't see the world wide web in its current shape
Exception Handling in Java: How-to Tutorial with Examples & Best Practices
As developers, we would like our users to interact with applications that run smoothly and without issues. We want the libraries that we create to be widely adopted and successful.
Understanding Java Garbage Collection Logging: What Are GC Logs and How to Analyze Them
When working with Java or any other JVM-based programming language we get certain functionalities for free. One of those functionalities is clearing the memory. If you’ve ever used languages like
SLF4J Tutorial: Loggers, Levels & How to Configure for Java Applications with Examples
Logging is a crucial part of the observability of your Java applications. Java logs combined with JVM metrics and traces give full observability into the application behavior and are invaluable
Logback Configuration Example: Tutorial on How to Use It for Logging in Java
Troubleshooting issues in your applications can be a complicated task requiring visibility into various components. In the worst-case scenario, to understand what is happening and why it is happening you
Java Logging Tutorial: Basic Concepts & Examples to Help You Log Efficiently
When it comes to troubleshooting Java application performance, JVM metrics are no longer enough. To fully understand the environment you also need Java logs and traces. Today, we're going to
Log4j2 Configuration Tutorial: Appenders, Levels, Examples
When it comes to troubleshooting application performance, the more information you have the better. Java logs combined with JVM metrics and traces give you full visibility into your Java applications.
Log4j Tutorial: How to Configure the Logger for Efficient Java Logging [Example]
Getting visibility into your application is crucial when running your code in production. What do we mean by visibility? Primarily things like application performance via metrics, application health, and availability,
Node.js Error Handling Made Easy: Best Practices On Just About Everything You Need to Know
Don't you hate it when you see an uncaughtException error pop up and crash your Node.js app? Yeah... I feel you. Can anything be worse? Oh yeah, sorry, unhandledRejection I
Solr Performance: Troubleshooting Solr Slow Queries Using Logs and Metrics
Let's say you get an alert that one or more queries is slow. Or that your users complain, whichever comes first 🙂 We've all been there… How do you find
Introducing MinIO Support in Sematext
Sematext Logs is a Log Management-as-a-service. Think of it as your own central location for logs in the cloud. If you prefer or need to keep logs in your own
Node.js Logging Tutorial: How to Check, Write & Debug [Best Practices]
Building SaaS products is hard. Making customers happy is even harder. I should know, I've built a start-up that failed! But, not everything is that bad. I learned a lot.
Understanding Logging Levels: What They Are & How To Use Them
Making sense out of logs is not an easy task. Log management solutions gather and accept data from multiple sources. Those sources can have different log structures, providing a different
What Is Log Analysis: Definition, Logging Use Cases & How-to Guide
Logs are one of the most valuable assets when it comes to IT system management and monitoring. As they record every action that took place on your network, logs provide
Java Logging Best Practices: 10+ Tips You Should Know to Get the Most Out of Your Logs
Having visibility into your Java application is crucial for understanding how it works right now, how it worked some time in the past and increasing your understanding of how it
What Are Linux Logs & How to Check Them: Logging Basics Explained with Examples
TL;DR note: if you want the bzip2 -9 version of this post, scroll down to the very last section for some quick pointers. If you want to learn a bit
Tutorial: Logging with journald
I'm sure you bumped into journald: it's what most distros use by default for system logging in Linux. Most applications running as a service will also log to the journal.
Logging vs Monitoring: How are They Different & Why You Need Both
By Chris Tozzi Logging or monitoring? If you deploy and manage an application, these are the two key techniques available to you for helping to ensure that the application meets
Shipping Kubernetes Nginx Ingress Logs Made Easy
Kubernetes is gaining popularity every day. Using an Ingress controller is the preferred method of allowing external access to the services in a cluster. This makes ingress logs incredibly important
Elasticsearch security: Authentication, Encryption, Backup
There’s no need to look outside the ELK Stack for apps to ensure data protection. Basic Elasticsearch Security features are free and include a lot of functionality to help you
Logstash Tutorial: Getting Started Guide for Shipping Logs
Looking to learn about Logstash as quickly as possible? This Logstash Tutorial is for you: we’ll install Logstash and push some Apache logs to Elasticsearch in less than 5 minutes.
14 Monitoring and Logging Best Practices and Standards for Monitoring
When managing cloud-native applications, it’s essential to have end-to-end visibility into what’s happening at any given time. This is especially true because of the distributed and dynamic nature of cloud-native
Monitoring Linux Audit Logs with auditd and Auditbeat
The Linux Audit framework is a kernel feature (paired with userspace tools) that can log system calls. For example, opening a file, killing a process or creating a network connection.
Monitoring Elasticsearch with Sematext
As shown in Elasticsearch Key Metrics, the setup, tuning, and operations of Elasticsearch require deep insights into the performance metrics such as index rate, query rate, query latency, merge times, and
Centralized AWS Lambda Logs with Kinesis and Serverless
The key to gaining serverless observability is sending all AWS Lambda Logs to a central location where you can later group, filter and make sense of them. Sematext is a full-stack
Elastic Stack Features (formerly X-Pack) Alternatives Comparison
Elastic Stack Features (formerly X-Pack) is an Elastic Stack extension that bundles security, alerting, monitoring, reporting, and graph capabilities. One could use either all or specific components. Elastic Stack Features as
5 Benefits to Run Elastic Stack in the Cloud
By Chris Riley What is the Elastic Stack? Elasticsearch, Logstash, and Kibana — the trio better known as Elastic Stack (or ELK, if you prefer a term that is now
Field Stats for Elasticsearch 6.x
We're excited to announce the release of the Field Stats API plugin for Elasticsearch. The Field Stats API used to be present from Elasticsearch 1.6 to 5.6, to provide efficient
Elasticsearch Ingest Node vs Logstash Performance
Unless you are using a very old version of Elasticsearch you’re able to define pipelines within Elasticsearch itself and have those pipelines process your data in the same way you’d
Recipe: How to integrate rsyslog with Kafka and Logstash
This recipe is similar to the previous rsyslog + Redis + Logstash one, except that we’ll use Kafka as a central buffer and connecting point instead of Redis. You’ll have
Handling Multiline Stack Traces with Logstash
Here at Sematext we use Java and rely on Elasticsearch for our hosted ELK logging SaaS, a lot. We like them so much that we regularly share our logging experience
Logtrail + Kibana = Retro Terminal Experience
Logtrail is a popular Kibana plugin that makes Kibana look like Papertrail. Sematext’s Logtrail view in Kibana gives you the terminal-like experience of exploring logs without the pain of needing
Docker Log Driver Alternatives
"Why does the 'docker logs' command fail?", is one of our frequently asked questions. The answer is simple and mentioned in the Docker documentation: "The docker logs command is not available for drivers
GDPR: Top 5 Logging Best Practices
The rather broad definition of personal data in the GDPR requires paying special attention to log data. GDPR and personal data in web server logs is a popular topic in
IoT: Air Pollution Tracking with Node.js, Elastic Stack, and MQTT
What can you do with a couple of IoT devices, Node.js, Elasticsearch, and MQTT? You can put together your own Internet of Things setup for measuring air pollution, like I
Rsyslog eBook: Centralized Logging with Rsyslog
Centralizing logs to Elasticsearch? Of course, the first log shipper that comes to mind is Logstash. When you get into it, you realize centralizing logs often implies a bunch of
AWS Elasticsearch Service vs. Elasticsearch on EC2
Many of our customers use AWS EC2. In the context of Elasticsearch consulting or support, one question we often get is: should we use AWS Elasticsearch Service instead of deploying Elasticsearch ourselves? The
Top 10 Docker Logging Gotchas
Docker changed not only how applications are deployed, it also changed the workflow for log management. Instead of writing logs to files, containers write logs to the console (stdout/stderr) and
Kafka Connect Elasticsearch: Consuming and Indexing with Kafka Connect
In the world of DevOps, metric collection, log centralization and analysis Apache Kafka is the most commonly used middleware. More specifically, it is used as a fast, persistent queue between
Embracing Kubernetes Successfully
Kubernetes is a really hot topic at the moment. All major cloud providers adopted it as a solution for deploying cloud native apps. Just a few weeks ago, AWS at
How to ship Kibana Server Logs to Elasticsearch
When dealing with log centralization in your organization you have to start with something. Often times people start by collecting logs for the most crucial pieces of software, and frequently
Logagent Meets Apache Kafka
This is a guest post from Filippo Balicchia. Filippo contributed Logagent plugins for Apache Kafka the details of which he is sharing in this post. Filippo is a software engineer
Shipping data to AWS Elasticsearch with Logagent
Elasticsearch is already quite popular and its popularity just keeps growing. Looking at Google Trends chart for the last 5 years shows this nicely: There are a number of reasons
Java 9 Elasticsearch Benchmark
TL;DR: The main question here is: How Does Java 9 Work with Elasticsearch 6? It works well, but don't expect miracles. Unless you're using G1, then there are some miracles. With
How to Detect Malicious Traffic in Your Server Logs: Sematext + Access Watch
Do you know what portion of your traffic comes from bots? Do you know which bots are good and which ones are bad? Do you know what the bad bots
Introducing Instant Templates and Mappings
Logsene, our hosted ELK stack now part of Sematext Cloud, exposes the Elasticsearch API. As a Logsene user you may or may not be aware of this. If you have
Metrics & Logs – Together or Separate?
Every modern organization depends on software, and where there is software there are metrics and logs and, one would hope, monitoring of these two critically important types of data. Operations
Search Guard – Security for Elasticsearch
Note: This is a guest post by Jochen Kressin, the CTO of floragunn GmbH, the makers of Search Guard, an open-source X-Pack Security alternative. Elasticsearch is a great piece of software.
Securing Elasticsearch and Kibana with Search Guard for free
Note: This is a guest post by Jochen Kressin, the CTO of floragunn GmbH, the makers of Search Guard, an open-source X-Pack Security alternative. In this article, we show you how
Docker Log Management & Enrichment
Over the last several months we’ve made all kinds of improvements to Sematext Docker Agent (SDA). If you’re not familiar with SDA yet, here it is in a nutshell: Sematext
S3 Archiving & Longer Retention for Logs
Need to have your recent logs searchable for your DevOps team(s) to troubleshoot issues, but also need to archive old logs for compliance reasons? Many organizations need that and
iOS SDK for Log Shipping & Analytics
Want to ship logs and other events from your iOS apps? We’ve open-sourced the iOS SDK for shipping logs from iOS apps to Sematext Cloud. This library not only
Android SDK for Log Shipping & Analytics
A few months back we’ve silently built and open-sourced an Android SDK for shipping logs from mobile apps to Sematext Cloud. This library not only lets you send your
Docker Security: Using Docker Secrets with Swarm
This post shows how to use Docker Secrets in Docker Swarm mode. For our example we’ll show how to use Docker Secrets to encrypt and safely store tokens used by
Network Security with Bro (now Zeek) and Elasticsearch
Intrusion detection systems generate highly valuable logs with network usage details and alerts. They collect vast amounts of data and typically store them in structures with a large number of
What is Syslog: Daemons, Message Formats and Protocols
Pretty much everyone's heard about syslog: with its roots in the 80s, it's still used for a lot of the log management done today. Mostly because of its long history, syslog
Exploring Windows Kernel with Fibratus and Sematext
This is a guest post by Nedim Šabić, developer of Fibratus, a tool for exploration and tracing of the Windows kernel. Unlike Linux / UNIX environments which provide a plethora of open
Elasticsearch for logs and metrics: A deep dive – Velocity 2016, O’REILLY CONFERENCES
We are known worldwide for our Elasticsearch, ELK stack and Solr consulting services, and we are always happy to help others improve their skills in these technologies, not only through
Tuning Solr & Pipeline for Logs – Video & Slides
Not everyone uses Splunk or ELK stack for logs. A few weeks ago, at the Lucene/Solr Revolution conference in Boston, we gave a talk about using Solr for logging, along
Elastic Stack Import-Export with Logstash & Logsene
In earlier posts, we explained how one can reindex data from one Elasticsearch cluster to another, or within the same Elasticsearch cluster, via tools like Logstash and rsyslog. The same
Sending AWS CloudWatch/VPC Logs to Logsene
Use-case: you're using AWS VPC and want visibility over the connection to your VPC. Which IPs are allowed or denied connections to certain ports, how much traffic goes through each
How to Ship Heroku Logs to Logsene / Managed ELK Stack
Update: We made it much easier to ship Heroku logs. Please read 5 Minute Recipe: Heroku Log Drain Setup for more details. Heroku is a cloud platform based on a managed
Sending your Windows Event Logs to Sematext using NxLog and Logstash
There are a lot of sources of logs these days. Some may come from mobile devices, some from your Linux servers used to host data, while other can be related to your
How to forward CloudTrail (or other logs from AWS S3) to Logsene
This recipe shows how to send CloudTrail logs (which are .gz logs that AWS puts in a certain S3 bucket) to a Logsene application, but should apply to any kinds
Using Grafana with Elasticsearch for Log Analytics
Grafana is an open-source alternative to Kibana. Grafana is best known as a visualization / dashboarding tool focused on graphing metrics from various data sources, such as InfluxDB. Even though
Presentation: Large Scale Log Analytics with Solr
In this presentation from Lucene/Solr Revolution 2015, Sematext engineers -- and Solr and centralized logging experts -- Radu Gheorghe and Rafal Kuć talk about searching and analyzing time-based data at
Recipe: Apache Logs + rsyslog (parsing) + Elasticsearch
More than two years ago we posted a recipe on how to centralize syslog in Elasticsearch in order to search and analyze them with Kibana, all by using only rsyslog.
Recipe: rsyslog + Redis + Logstash
OK, so you want to hook up rsyslog with Logstash. If you don't remember why you want that, let me give you a few hints: Logstash can do lots of
Introducing Logsene CLI
[Note: this post was written by Sematext engineer Marko Bonaći] In vino veritas, right? During a recent team gathering in Kraków, Poland, and after several yummy bottles of țuică, vișinată,