The foremost use of syslog is for systems management. Proactive syslog monitoring really pays off because it significantly reduces downtime of servers and other devices in your infrastructure. Then there is the cost savings from preventing loss of productivity that usually accompanies reactive troubleshooting.
Alerting is another good use of syslog. You have a variety of options and severity levels that you can choose in setting up syslog alerts, including emergency, critical, warning, error, and so on. Also, alerts have fine points like host details, time period, and log/message details. The following are different areas where syslog alerting is useful:
- Network alerting: Syslog is extremely helpful in identifying critical network issues. For example, it can detect fabric channel errors on a switch fabric module. This is one of many such warnings or errors that other forms of monitoring metrics cannot detect.
- Security alerting: Syslog messages provide detailed context of security events. Security admins can use syslog to recognize communication relationships, timing, and in some cases, an attacker’s motive and/or tools.
- Server alerting: Syslog can alert on server startups, clean server shutdowns, abrupt server shutdowns, configuration reloads and failures, runtime configuration impact, resource impact, and so on. All these alerts can help detect if the servers are alive. Syslog also helps detect failed connections. Server alerts are always useful, especially when you oversee hundreds of servers.
- Application alerting: You need application alerting for troubleshooting live issues. Applications create logs in different ways—some through syslog. When you run a Web application, dozens of logs are written in the log folder. To get real-time monitoring, you need a syslog monitoring solution that can observe changes in the log folder.
Monitoring high-availability (HA) servers is important and another good use of syslog. However, not all the logs from the HA server are important. You just need to monitor the logs that are troublesome. However, in case of a HA server failure, you still need all the logs from the server. The solution for this is to have a dedicated syslog server for your HA cluster.
Despite the importance of proactive monitoring, some logs can only be analyzed later. Sometimes an alert or an error sends only basic details that are located in the local memory buffer. For detailed analysis, you need to dig into the historical syslog reports using any syslog analysis tool, like LogZilla®, Kiwi Syslog®, syslog-ng, etc. Historical syslog data can often provide comprehensive details, like configuration changes, high momentary error rates, a sustained abnormal condition, etc., that cannot be shown using other forms of monitoring.
Proactive syslog monitoring and troubleshooting reduces trouble tickets because you detect and resolve issues before they become trouble tickets. A synchronous Web dashboard, alerting system, and log storage (with search options) are the basic features of any syslog monitoring tool. Moreover, integrating the syslog monitoring tool with other infrastructure management tools adds value to your syslog monitoring.