InterScan Web Security Virtual Appliance (IWSVA) 6.5 performance problem

We had some trouble with IWSVA to use the full download speed from our internet connection. Downloads are limit to 5 MB per second and not faster. After contactig support and a remote session. The support send me this solution.

After this, we can use our full internet speed with IWSVA



From @sysctl.conf in CDT:

By default, in IWSVA, window scaling is disabled.


– Set the TCP Windows Scaling from 0 to 1.

  1. Login IWSVA shell


  1. Open /etc/sysctl.conf


  1. Find and change the following parameter to the coresponding value.




  1. Run command “sysctl -p”