How to easily view real-time log entries with tail in Linux – Guide
IT departments in most companies deal with numerous activities, both routine and rare in nature. The common goal of all IT teams is to keep their business running with optimal utilization of IT resources. However, ensuring high availability for business applications and monitoring the health of the network and infrastructure is not a simple task. IT teams need to monitor different endpoints and dashboards to control multiple servers, network equipment, user devices, applications, and more. Although the tools and processes for monitoring corporate IT environments have evolved significantly, certain practices and utilities still prove to be helpful in troubleshooting basic issues. One such utility is log tail, which helps to monitor system logs. In this article, we will discuss how to real-time tail logs and what tools can be useful for this purpose.
Traditional head and tail commands
Most system administrators used the “head” and “tail” commands on their Linux terminals. The head command prints the first 10 lines of a text file, while the tail command prints the last 10 lines of a text file. If necessary, you can change the number of lines printed using the -n argument. For example, the command “tail -n 15 example.txt” will print the last 15 lines of the text file. These commands are particularly useful for scripting and system administration purposes. Like most log files and plain text files, the commands work equally well.
Following a Log Tail
You can monitor for new additions to a text file using the follow operator or the -f option. The tail -f command prints the last 10 lines of a text or log file and then waits for new additions to the file to print it in real time. This allows administrators to see a log message as soon as a system creates it. The tail -f command continues to print messages and you have to stop the session with a Ctrl + C command. Since logs tend to grow quickly, it’s important to focus only on the most critical log messages, so system administrators also use the “grep” command along with tail -f command to filter log messages.
Challenges with real-time log monitoring
As discussed above, the tail -f command, commonly referred to as live tail, helps monitor logs in real time. Administrators used to directly monitor a local machine or ssh on some remote servers to access their logs. However, modern IT environments are highly complex, containing multiple physical and virtual servers and cloud-based resources. In such an environment, it is not possible to track individual log tails at different terminals simultaneously.
How to Simplify real-time log monitoring
To solve the above challenge, organizations rely on centralized log management. It involves aggregating logs from different sources and turning them into a common format to monitor them in a single window. Cloud-based log management tools and log-as-a-service (LaaS) providers help users collect a large volume of logs, analyze them in different fields, and filter, search, track and view them for analysis. With these tools, they can also define up alerts for critical events to expedite response.
Common Tools for Final Records
Elastic Stack or ELK-Stack is a common open source solution consisting of tools like Elasticsearch, Logstash and Kibana. Elasticsearch is the core of the solution and offers multithreaded nodes for searching logs, Logstash is the log aggregator and Kibana helps to view log messages. These tools help organizations manage and analyze a large volume of logs. Teams can also monitor their logs in real-time using these tools. These open source tools offer a high level of flexibility for organizations to build a monitoring system based on their requirements. However, organizations sometimes need to go beyond these tools to achieve optimal performance. For example, in many cases they need to install a message queue for log persistence. Choosing whether to create a self-hosted configuration or use the cloud to install the ELK stack is another complex decision, without a single answer. Organizations should consider these and many other configuration challenges before choosing Elastic Stack for log monitoring. However, as discussed earlier, organizations can also choose cloud-based business log management solutions that offer simpler configuration, greater scalability, and a lower total cost of ownership. Tools like SolarWinds® Loggly®, LogDNA, Sumo Logic and Splunk are some highly rated log viewers and analyzers on the market. However, if you are looking for a simple yet powerful tool for tracking logs, we recommend SolarWinds Papertrail.
papertrail
Papertrail is a cloud-based log management tool and is configurable up typically within minutes without facing any complex configuration or initial infrastructure provisioning requirement. The tool allows teams to collect logs from a wide variety of sources, without the need to install agents. As logs are collected, they can be viewed in an event viewer in near real-time. Administrators can view the live tail, click on certain elements of their log messages (eg IP address, event ID, HTTP response code, etc.) to filter them. Papertrail also allows teams to save critical research and generate alerts about an event. Alerts can be forwarded to a messaging service such as Slack or Hipchat or can be sent via email, depending on staff preference. Searching for log messages in Papertrail is easy as it supports familiar searches and you don’t need to learn any complex query syntax. You can get a free trial of Papertrail to rate your features and choose a superior plan according to your organization’s requirements.
Conclusion
By correlating logs from multiple sources, teams can gain a better understanding of their IT environments, get to the root cause of issues faster, and find patterns to help predict future events. Tools like Papertrail are built to simplify real-time logging and monitoring in production environments.
Final note
I hope you like the guide How to easily view real-time log entries with tail in Linux. In case if you have any query regards this article you may ask us. Also, please share your love by sharing this article with your friends.