mod_ext_filter is not installed. But why? I need it for w3tc.
I’m not familiar with this extension, but judging by the documentation, it allows you to process output of a web request through an external program?
If so, enabling it would be a big security risk, because it would allow you to execute arbitrary commands on the server. And it also circumvents many of the resource restrictions we have placed on (especially) PHP.
So we cannot enable this extension on our servers, and I don’t see why any web hosting provider with concern for security and performance would allow this.
So I’m sorry to say you cannot use the features of W3 Total Cache which require these server modules.
We’ve got DDOS attack itself is enough :j
with enabling mod_ext_filter that will become a big risk as admin said.