SD-WAN - GRE tunnel down after edge software upgrade to 5.2.3.0, due to a space in the GRE tunnel IP configuration on the VCO.

Products

• VMware VeloCloud SD-WAN

Issue/Introduction

The Edge GRE tunnel (CSS - Zscaler) go down after upgrading the Edge software version from anything lower than 5.1.x, to 5.1.x through 5.2.x.

Cause

When the GRE tunnel IP address as configured in the VCO has an extra space in it, this causes the edge, after upgrading, to incorrectly parse the GRE destination IP address, resulting in GRE packets being sent to the IP address 0.0.0.0 instead of the correct destination IP.

In contrast, the same GRE configuration is parsed correctly by the edge versions 4.3.1 and 5.0.

 

Sample incorrect config in the new VCO UI :

 

             

Resolution

Remove the extra space at the end of the GRE server IP address configuration and save the config in the new VCO UI.

This issue is being tracked under software defect 146588.