varnish3 and drupal7 cache problem

I have used varnish module for my website,
it works well for the front page,
but for node page , it doesn't cached at all, (http://www.inkebook.com/335475-made-india-decolonizations-queer-sexualit...)
this is the response head :
X-Varnish-Cache: MISS

Could you take a look at it ? Thanks !

Accept-Ranges bytes
Age 0
Cache-Control no-cache, must-revalidate, post-check=0, pre-check=0
Connection keep-alive
Content-Encoding gzip
Content-Language und
Content-Length 9140
Content-Type text/html; charset=utf-8
Date Wed, 09 May 2012 11:22:26 GMT
Etag "1336562545"
Last-Modified Wed, 09 May 2012 11:22:25 +0000
Link http://www.inkebook.com/node/335475; rel="shortlink",http://www.inkebook.com/335475-made-india-decolonizations-queer-sexualities-transnational-projects-repost; rel="canonical"
Server Apache/2.2.20 (Ubuntu)
Vary Accept-Encoding
Via 1.1 varnish
X-Drupal-Cache MISS
X-Varnish 680185702
X-Varnish-Cache MISS

my default.vcl

This is a basic VCL configuration file for varnish. See the vcl(7)

man page for details on VCL syntax and semantics.

Default backend definition. Set this to point to your content

server.

include "acl.vcl";
include "backends.vcl";

Respond to incoming requests.

sub vcl_recv {
if (req.request == "GET" && req.url ~ "^/varnishcheck$") {
error 200 "Varnish is Ready";
}

# Allow the backend to serve up stale content if it is responding slowly.
if (!req.backend.healthy) {
# Use anonymous, cached pages if all backends are down.
unset req.http.Cookie;
if (req.http.X-Forwarded-Proto == "https") {
set req.http.X-Forwarded-Proto = "http";
}
set req.grace = 30m;
} else {
set req.grace = 15s;
}

# Allow PURGE from localhost and 192.168.0.0/24
if (req.request == "PURGE") {
if (!client.ip ~ purge) {
error 405 "Not allowed.";
}
return (lookup);
}

# Get ride of progress.js query params
if (req.url ~ "^/misc/progress.js\?[0-9]+$") {
set req.url = "/misc/progress.js";
}

# If global redirect is on
#if (req.url ~ "node\?page=[0-9]+$") {
# set req.url = regsub(req.url, "node(\?page=[0-9]+$)", "\1");
# return (lookup);
#}

# Do not cache these paths.
if (req.url ~ "^/status.php$" ||
req.url ~ "^/update.php$" ||
req.url ~ "^/ooyala/ping$" ||
req.url ~ "^/admin" ||
req.url ~ "^/admin/.$" ||
req.url ~ "^/user" ||
req.url ~ "^/user/.$" ||
req.url ~ "^/users/.$" ||
req.url ~ "^/info/.$" ||
req.url ~ "^/flag/.$" ||
req.url ~ "^./ajax/.$" ||
req.url ~ "^./ahah/.*$") {
return (pass);
}

# Pipe these paths directly to Apache for streaming.
if (req.url ~ "^/admin/content/backup_migrate/export") {
return (pipe);
}

# Do not allow outside access to cron.php or install.php.
if (req.url ~ "^/(cron|install).php$" && !client.ip ~ internal) {
# Have Varnish throw the error directly.
error 404 "Page not found.";
# Use a custom error page that you've defined in Drupal at the path "404".
# set req.url = "/404";
}

# Handle compression correctly. Different browsers send different
# "Accept-Encoding" headers, even though they mostly all support the same
# compression mechanisms. By consolidating these compression headers into
# a consistent format, we can reduce the size of the cache and get more hits.=
# @see: http:// varnish.projects.linpro.no/wiki/FAQ/Compression
if (req.http.Accept-Encoding) {
if (req.http.Accept-Encoding ~ "gzip") {
# If the browser supports it, we'll use gzip.
set req.http.Accept-Encoding = "gzip";
}
else if (req.http.Accept-Encoding ~ "deflate") {
# Next, try deflate if it is supported.
set req.http.Accept-Encoding = "deflate";
}
else {
# Unknown algorithm. Remove it and send unencoded.
unset req.http.Accept-Encoding;
}
}

# Always cache the following file types for all users.
if (req.url ~ "(?i).(png|gif|jpeg|jpg|ico|swf|css|js)(\?[a-z0-9]+)?$") {
unset req.http.Cookie;
}

# Remove all cookies that Drupal doesn't need to know about. ANY remaining
# cookie will cause the request to pass-through to a backend. For the most part
# we always set the NO_CACHE cookie after any POST request, disabling the
# Varnish cache temporarily. The session cookie allows all authenticated users
# to pass through as long as they're logged in.
#
# 1. Append a semi-colon to the front of the cookie string.
# 2. Remove all spaces that appear after semi-colons.
# 3. Match the cookies we want to keep, adding the space we removed
# previously, back. (\1) is first matching group in the regsuball.
# 4. Remove all other cookies, identifying them by the fact that they have
# no space after the preceding semi-colon.
# 5. Remove all spaces and semi-colons from the beginning and end of the
# cookie string.
if (req.http.Cookie) {
set req.http.Cookie = ";" + req.http.Cookie;
set req.http.Cookie = regsuball(req.http.Cookie, "; +", ";");
set req.http.Cookie = regsuball(req.http.Cookie, ";(S{1,2}ESS[a-z0-9]+|NO_CACHE)=", "; \1=");
set req.http.Cookie = regsuball(req.http.Cookie, ";[^ ][^;]*", "");
set req.http.Cookie = regsuball(req.http.Cookie, "^[; ]+|[; ]+$", "");

if (req.http.Cookie == "") {
  # If there are no remaining cookies, remove the cookie header. If there
  # aren't any cookie headers, Varnish's default behavior will be to cache
  # the page.
  unset req.http.Cookie;
}
else {
  # If there is any cookies left (a session or NO_CACHE cookie), do not
  # cache the page. Pass it on to Apache directly.
  return (pass);
}

}

## From default below ##
if (req.restarts == 0) {
if (req.http.x-forwarded-for) {
set req.http.X-Forwarded-For =
req.http.X-Forwarded-For + ", " + client.ip;
} else {
set req.http.X-Forwarded-For = client.ip;
}
}
if (req.request != "GET" &&
req.request != "HEAD" &&
req.request != "PUT" &&
req.request != "POST" &&
req.request != "TRACE" &&
req.request != "OPTIONS" &&
req.request != "DELETE") {
/* Non-RFC2616 or CONNECT which is weird. /
return (pipe);
}
if (req.request != "GET" && req.request != "HEAD") {
/ We only deal with GET and HEAD by default /
return (pass);
}
## Unset Authorization header if it has the correct details...
#if (req.http.Authorization == "Basic ") {
# unset req.http.Authorization;
#}
if (req.http.Authorization || req.http.Cookie) {
/ Not cacheable by default */
return (pass);
}
return (lookup);
}

sub vcl_pipe {
# Note that only the first request to the backend will have
# X-Forwarded-For set. If you use X-Forwarded-For and want to
# have it set for all requests, make sure to have:
set bereq.http.connection = "close";
# here. It is not set by default as it might break some broken web
# applications, like IIS with NTLM authentication.
}

Routine used to determine the cache key if storing/retrieving a cached page.

sub vcl_hash {
if (req.http.X-Forwarded-Proto == "https") {
hash_data(req.http.X-Forwarded-Proto);
}
}

sub vcl_hit {
if (req.request == "PURGE") {
purge;
error 200 "Purged.";
}
}

sub vcl_miss {
if (req.request == "PURGE") {
purge;
error 200 "Purged.";
}
}

Code determining what to do when serving items from the Apache servers.

sub vcl_fetch {
# Don't allow static files to set cookies.
if (req.url ~ "(?i).(png|gif|jpeg|jpg|ico|swf|css|js)(\?[a-z0-9]+)?$") {
# beresp == Back-end response from the web server.
unset beresp.http.set-cookie;
}
else if (beresp.http.Cache-Control) {
unset beresp.http.Expires;
}

if (beresp.status == 301) {
set beresp.ttl = 1h;
return(deliver);
}

## Doesn't seem to work as expected
#if (beresp.status == 500) {
# set beresp.saintmode = 10s;
# return(restart);
#}

# Allow items to be stale if needed.
set beresp.grace = 1h;
}

Set a header to track a cache HIT/MISS.

sub vcl_deliver {
if (obj.hits > 0) {
set resp.http.X-Varnish-Cache = "HIT";
}
else {
set resp.http.X-Varnish-Cache = "MISS";
}
}

In the event of an error, show friendlier messages.

sub vcl_error {
set obj.http.Content-Type = "text/html; charset=utf-8";
set obj.http.Retry-After = "5";
synthetic {"
<?xml version="1.0" encoding="utf-8"?>

"} + obj.status + " " + obj.response + {"

Error "} + obj.status + " " + obj.response + {"

"} + obj.response + {"

Guru Meditation:

XID: "} + req.xid + {"

---

Varnish cache server

"};
return (deliver);
}

Below is a commented-out copy of the default VCL logic. If you

redefine any of these subroutines, the built-in logic will be

appended to your code.

sub vcl_recv {

if (req.restarts == 0) {

if (req.http.x-forwarded-for) {

set req.http.X-Forwarded-For =

req.http.X-Forwarded-For + ", " + client.ip;

} else {

set req.http.X-Forwarded-For = client.ip;

}

}

if (req.request != "GET" &&

req.request != "HEAD" &&

req.request != "PUT" &&

req.request != "POST" &&

req.request != "TRACE" &&

req.request != "OPTIONS" &&

req.request != "DELETE") {

/* Non-RFC2616 or CONNECT which is weird. */

return (pipe);

}

if (req.request != "GET" && req.request != "HEAD") {

/* We only deal with GET and HEAD by default */

return (pass);

}

if (req.http.Authorization || req.http.Cookie) {

/* Not cacheable by default */

return (pass);

}

return (lookup);

}

sub vcl_pipe {

# Note that only the first request to the backend will have

# X-Forwarded-For set. If you use X-Forwarded-For and want to

# have it set for all requests, make sure to have:

# set bereq.http.connection = "close";

# here. It is not set by default as it might break some broken web

# applications, like IIS with NTLM authentication.

return (pipe);

}

sub vcl_pass {

return (pass);

}

sub vcl_hash {

hash_data(req.url);

if (req.http.host) {

hash_data(req.http.host);

} else {

hash_data(server.ip);

}

return (hash);

}

sub vcl_hit {

return (deliver);

}

sub vcl_miss {

return (fetch);

}

sub vcl_fetch {

if (beresp.ttl <= 0s ||

beresp.http.Set-Cookie ||

beresp.http.Vary == "*") {

/*

* Mark as "Hit-For-Pass" for the next 2 minutes

*/

set beresp.ttl = 120 s;

return (hit_for_pass);

}

return (deliver);

}

sub vcl_deliver {

return (deliver);

}

sub vcl_error {

set obj.http.Content-Type = "text/html; charset=utf-8";

set obj.http.Retry-After = "5";

synthetic {"

<?xml version="1.0" encoding="utf-8"?>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

"} + obj.status + " " + obj.response + {"

Error "} + obj.status + " " + obj.response + {"

"} + obj.response + {"

Guru Meditation:

XID: "} + req.xid + {"

---

Varnish cache server

"};

return (deliver);

}

sub vcl_init {

return (ok);

}

sub vcl_fini {

return (ok);

}