Significance of hash_data and the rest of the vcl ecosystem.

[Kim Eik]

Im trying to figure out the varnish config, and what the
ramifications of the different config options are.

as far as i can figure out the hash_data will append information to
the hash so that we can create a greater granularity in our cache. One
example might be to create a separate cache for each different user
identified by JSESSIONID.

However, are other commands like ban() affected by the hash_data?

so if i were to ban_url(/some/url) would it only ban /some/url for the
JSESSIONID hash it was operating under or would it affect all requests
against /some/url regardless?