Unable to change primary IP for SolusIO VPS if the previous primary IP is from IP block with different Gateway IP: Server Error

Symptoms 

• Unable to change primary IP for SolusIO VPS if the previous primary IP is from IP block with different Gateway IP. The following error is displayed on attempt to change primary IP at SolusIO > Virtual Servers > VPS > Networking:

  SVM_ERROR: Server Error

• The following error is displayed in solus_api container log on SolusIO management node:

  # docker container logs $(docker ps -q -f name=solus_api | head -n1)
  ...
  production.ERROR: New primary IP address has 203.0.113.1 gateway, but should be 192.0.2.1. {"userId":1,"exception":"[object] (Api\\v1\\ComputeResourceVm\\Services\\Exceptions\\DifferentGatewayException(code: 0): New primary IP address has 203.0.113.1 gateway, but should be 192.0.2.1. at /var/www/backend/api/v1/ComputeResourceVm/Services/ComputeResourceVmService.php:910)

Cause

SolusIO bug #SIO-4087 which was fixed in SolusIO version 1.1.23509

Resolution

Update SolusIO to the latest mainline version.