Varnish.4.x not caching range requests - caching

Question

We are trying to get Varnish to cache range requests. We are using Varnish 4.0.
We the following configurations
vcl 4.0;
import std;
# Default backend definition. Set this to point to your content server.
backend default {
.host = "194.142.x.x";
.port = "8008";
}
sub vcl_recv {
if (req.url ~ "(?i)\.(png|avi|mkv|mp4)(\?[a-z0-9]+)?$") {
unset req.http.Cookie;
}
# Happens before we check if we have this in cache already.
#
# Typically you clean up the request here, removing cookies you don't need,
# rewriting the request, etc.
set req.http.host = regsub(req.http.host, "v\.","\rms\.");
std.log("REWRITED TO"+req.http.host+" "+req.url);
}
sub vcl_backend_response {
# Happens after we have read the response headers from the backend.
#
# Here you clean the response headers, removing silly Set-Cookie headers
# and other mistakes your backend does.
}
sub vcl_deliver {
# Happens when we have all the pieces we need, and are about to send the
# response to the client.
#
vcl 4.0;
import std;
# Default backend definition. Set this to point to your content server.
backend default {
.host = "194.142.x.x";
.port = "8008";
}
sub vcl_recv {
if (req.url ~ "(?i)\.(png|avi|mkv|mp4)(\?[a-z0-9]+)?$") {
unset req.http.Cookie;
}
# Happens before we check if we have this in cache already.
#
# Typically you clean up the request here, removing cookies you don't need,
# rewriting the request, etc.
set req.http.host = regsub(req.http.host, "v\.","\rms\.");
std.log("REWRITED TO"+req.http.host+" "+req.url);
}
sub vcl_backend_response {
# Happens after we have read the response headers from the backend.
#
# Here you clean the response headers, removing silly Set-Cookie headers
# and other mistakes your backend does.
}
sub vcl_deliver {
# Happens when we have all the pieces we need, and are about to send the
# response to the client.
#
how ever range requests are taking too long to be served so we feel its not being cached as the original server is hit.

Answer 1

Can you solve this...?
I'm pretty sure the block config:
if (req.url ~ "(?i)\.(png|avi|mkv|mp4)(\?[a-z0-9]+)?$") {
unset req.http.Cookie;
}
# Happens before we check if we have this in cache already.
#
# Typically you clean up the request here, removing cookies you don't need,
# rewriting the request, etc.
set req.http.host = regsub(req.http.host, "v\.","\rms\.");
std.log("REWRITED TO"+req.http.host+" "+req.url);
Are in wrong position, needs to be in vcl_backend_response not in vcl_recv

Answer 2

Caching partial objects with varnish 4.0
sub vcl_recv {
if (req.http.Range ~ "bytes=") {
set req.http.x-range = req.http.Range;
}
}
sub vcl_hash {
if (req.http.x-range ~ "bytes=") {
hash_data(req.http.x-range);
unset req.http.Range;
}
}
sub vcl_backend_fetch {
if (bereq.http.x-range) {
set bereq.http.Range = bereq.http.x-range;
}
}
sub vcl_backend_response {
if (bereq.http.x-range ~ "bytes=" && beresp.status == 206) {
set beresp.ttl = 10m;
set beresp.http.CR = beresp.http.content-range;
}
}
sub vcl_deliver {
if (resp.http.CR) {
set resp.http.Content-Range = resp.http.CR;
unset resp.http.CR;
}
}