What is the difference between SNMP Trap and Syslog?

System administrators use Syslog or SNMP Trap for monitoring. Both standards provide very similar monitoring information, but with different functions.

Syslog can be used as a troubleshooting tool and is used when logs are needed for investigation. Although Syslog can be used for real-time summaries, it is usually only used for quick historical events. SNMP Traps can be used for device-based events. It provides real-time information and allows for better management. In most cases, using a combination of the two is the best solution depending on the specific situation.

What is Syslog?

Syslog is a message logging protocol used to exchange logs of different events from multiple devices. It consists of three parts: the Syslog device that generates logs, the Syslog relay that forwards the logs to the collector, and the Syslog collector (or server) that receives and stores the logs.

The format of each log includes timestamp, host IP address, event message, severity, diagnostics, etc. Syslog allows you to choose the type of information captured. These logs can be anything from ACL events, configuration changes, authentication attempts, etc.

The main function of Syslog is to collect logs for troubleshooting and monitoring.

What is SNMP Trap?

SNMP Trap is one of the five (Trap, Get, Get-Next, Get-Response, Set) event message types used by SNMP. SNMP Trap is generated by SNMP-enabled devices (agents) and sent to collectors (managers). SNMP Trap notifies SNMP managers in real time when important events occur. SNMP Trap uses thresholds configured on the agent. When an agent exceeds a threshold, an SNMP Trap is triggered and sent to the manager.

SNMP Traps send data using numeric classes that are converted using SNMP MIBs (Management Information Bases). An SNMP manager does not request SNMP Traps, but can use SNMP Get messages (including other software) to poll information from an agent.

The main function of SNMP Trap is to collect events in real time for management and monitoring.

Similarities between Syslog and SNMP Trap

Both are alert messages generated from remote devices and sent to a central collector; both provide similar "monitoring" information; both act on demand, and are not solicited.

Difference between Syslog and SNMP Trap

In general, the SNMP protocol defines a method for remote monitoring and configuration through other types of messages. Syslog is just an alert mechanism (same as SNMP Trap), and Syslog does not define any standards for remote configuration.

Syslog provides more detailed information in the log messages. Although not a standard, Syslog is often used for troubleshooting and debugging, while SNMP Traps are used for device management and reporting.

Syslog Messages vs. SNMP MIB Requests: SNMP Get Request messages can be used to poll from the agent using the local MIB. Syslog cannot be used to poll for information.