Ban URL - req.backend unsupported?

[Cedric Jeanneret]

Hello!

I'm trying to ban some content matching the configured req.backend, but it seems it's not working as expected:

varnish> ban req.backend == "foo_bar" && req.url ~ "^/baz/foo"
106        
unknown or unsupported field "req.backend"

I thought the ban syntax would take any of VCL variable (req.url, obj.set-cookie, req.http.host… and so on)… ?

Any help would be appreciated.

Thanks in advance.

Cheers,

C.