WAN Monitoring

WAN monitoring helps monitor the availability and round-trip time (RTT) of WAN links between a Cisco router and a given destination. Site24x7 leverages Cisco's Internet Protocol Service Level Agreement (IP SLA) technology to detect delays in RTT and send proactive alerts that help network administrators resolve issues quickly.

Use case

Consider an e-commerce organization that has multiple branch offices. Even a one-minute outage will severely disrupt the organization. With WAN monitoring, if there's any delay in the round-trip time, the network administrator will receive an alert immediately, provided the devices are added as WAN monitors. This helps admins to quickly resolve any issues before they turn into major outages. By reviewing the details available on the monitor summary page, they can get to the issue's root cause. For example, there may be a redirection by the ISP which causes a traffic delay. In that case, the network administrator can inform the ISP that there's a delay due to the redirection and get the issue resolved before it causes a significant impact.

How it works

WAN monitoring measures the time taken for data to travel between any two points in a network by using Cisco's IP SLA. Once you've added the device for WAN monitoring, you will start receiving alerts whenever there's any issue on the WAN link. You can configure settings to receive alerts on your preferred channel. The monitor summary page also provides detailed information about the WAN link. This helps network administrators obtain real-time visibility into RTT delays and performance of the selected WAN link.

Prerequisites

• The source device must be a Cisco router with IP SLA.
• The source device should only be added using the SNMP v1 or v2c protocols.
  
  

  Ensure you have read and write permissions on the device.
• The source device must be added as a network monitor in Site24x7. However, this is not mandatory for the destination device. Even if the destination device is added as a network monitor or any other monitor, it will have no bearing on WAN monitoring.
• The other device must support RFC 862: Echo protocol. Though it is not mandatory, we recommend using a Cisco device as the other endpoint.

WAN monitor configurations are stored in the running configuration of the device during the addition of the monitor to Site24x7. This will be lost once the device reboots. To save it permanently, copy the configuration from running to startup configuration by executing the below command in the device default mode:

copy running-config startup-config

If the device is also added in the Network Configuration Management (NCM) module, a backup will be taken whenever there's an update to the device configuration. You'll receive an alert if there's a difference between the configurations.

Next steps

• Adding a WAN Monitor
• Performance Metrics of a WAN Monitor
• Threshold and Availability Profiles for a WAN Monitor