Fast and Furious: Examining the 30-Second Load Interval

Posted on in networking

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The load-interval command in Cisco IOS allows network administrators to define the time frame used to calculate interface load statistics. By default, this interval is set to 5 minutes, providing a broad overview of traffic patterns. However, some situations might call for a more granular view. Here's a breakdown of the pros and cons of setting load-interval to 30 seconds:


  • Increased Reactivity: A 30-second interval offers a closer look at real-time traffic fluctuations. This can be crucial for identifying short bursts of high traffic that might be missed with a longer interval. This is particularly beneficial for troubleshooting network congestion caused by spiky applications like video conferencing or real-time data feeds.
  • Faster Troubleshooting: With a more up-to-date picture of interface load, administrators can pinpoint issues quicker. This is especially helpful in dynamic environments where traffic patterns can change rapidly.
  • Improved Monitoring in Labs: In network labs where network behavior might be accelerated, a shorter load-interval allows for a more accurate representation of traffic patterns within the compressed timeframe.


  • Increased Processing Overhead: Calculating statistics more frequently consumes additional processing power on the network device. This might be a concern for older or resource-constrained routers or switches.
  • Granularity vs. Clarity: While a 30-second interval reveals short-term fluctuations, it might obscure long-term trends. Network administrators might struggle to identify sustained load issues when presented with a rapid stream of data points.
  • False Alarms: Short-term spikes in traffic might trigger unnecessary alerts or troubleshooting efforts due to the heightened sensitivity of the monitoring.

When to Use load-interval 30

  • Troubleshooting network congestion caused by bursty traffic patterns.
  • Monitoring dynamic network environments.
  • Network labs with simulated traffic patterns.

When to Avoid load-interval 30

  • Resource-constrained network devices.
  • Situations where long-term load trends are critical.
  • Environments with minimal risk of bursty traffic.


The decision to set load-interval to 30 seconds requires careful consideration of the network's specific needs and limitations. For situations requiring real-time insights into short-term traffic fluctuations, it can be a valuable tool. However, in environments prioritizing long-term trends or with limited processing power, the default 5-minute interval might be more suitable.

Additional Considerations

  • It's important to monitor the impact of a shortened load-interval on device performance.
  • Utilize other monitoring tools like show interface in conjunction with load-interval for a comprehensive understanding of network traffic.
  • Consider using a tiered approach, setting load-interval to 30 seconds on critical interfaces and leaving others at the default for a balance between granularity and resource usage.

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