Communication Delay via Symantec Cloud Secure Web Gateway

Products

• VMware VeloCloud SD-WAN

Issue/Introduction

The bandwidth of the IPsec tunnel between the Symantec Cloud Secure Web Gateway (SWG) and Edge/VCG is 1Gbps. When the volume of traffic passing through the IPsec tunnel increases, communication delays or packet loss may occur.

Environment

VeloCloud SD-WAN
Non SD-WAN Destination via Edge/Gateway connected to SWG

Resolution

This article outlines the method to check the bandwidth usage between SWG and Edge/VCG from the VCO interface.

The following outlines the procedure for checking when connected to SWG via Non SD-WAN Destination via Gateway, using it as an example:

1. Monitor > Network Services > Select the target NSD via Gateway > Select the Monitoring tab
2. Specify the date and time for which you want to check the bandwidth usage
3. Confirm that the graph is displayed as 'Bytes Received/Sent'
4. Hover the mouse cursor over the graph to check the data display interval and the number of bytes transferred between the two adjacent data points. For example, in the following case, 23.342 GByte of data was transferred between 9:10 AM and 9:15 AM (five minutes).
   
5. Calculate the bandwidth usage:
   23.342 GByte * 8 / 300 sec = 0.62245 Gbps

From the above, the average bandwidth usage over the five-minute period is 0.62245 Gbps. If this value is close to the upper limit of 1 Gbps, it is possible that packet delays or drops are occurring due to insufficient bandwidth.