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 <section id="vcl-variables">
<h1>VCL-Variables<a class="headerlink" href="#vcl-variables" title="Link to this heading">¶</a></h1>
<section id="the-complete-album">
<h2>The complete album<a class="headerlink" href="#the-complete-album" title="Link to this heading">¶</a></h2>
<dl class="field-list simple">
<dt class="field-odd">Manual section:</dt>
<dd class="field-odd">7
</dd>
</dl>
<section id="description">
<h3>DESCRIPTION<a class="headerlink" href="#description" title="Link to this heading">¶</a></h3>
This is a list of all variables in the VCL language.
Variable names take the form <code class="docutils literal notranslate">scope.variable[.index]</code>, for instance:
<div class="highlight-default notranslate"><div class="highlight"><pre>req.url
beresp.http.date
client.ip
</pre></div>
</div>
Which operations are possible on each variable is described below,
often with the shorthand “backend” which covers the <code class="docutils literal notranslate">vcl_backend_* {}</code>
subroutines and “client” which covers the rest, except <code class="docutils literal notranslate">vcl_init {}</code>
and <code class="docutils literal notranslate">vcl_fini {}</code>.
<section id="local-server-remote-and-client">
<h4>local, server, remote and client<a class="headerlink" href="#local-server-remote-and-client" title="Link to this heading">¶</a></h4>
These variables describe the network connection between the
client and varnishd.
Without PROXY protocol:
<div class="highlight-default notranslate"><div class="highlight"><pre> client server
 remote local
 v v
CLIENT ------------ VARNISHD
</pre></div>
</div>
With PROXY protocol:
<div class="highlight-default notranslate"><div class="highlight"><pre> client server remote local
 v v v v
CLIENT ------------ PROXY ------------ VARNISHD
</pre></div>
</div>
client.identity
<blockquote>
<div>Type: STRING
Readable from: client, backend
Writable from: client
Identification of the client, used to load balance
in the client director. Defaults to <code class="docutils literal notranslate">client.ip</code>
This variable can be overwritten with more precise
information, for instance extracted from a <code class="docutils literal notranslate">Cookie:</code>
header.
</div></blockquote>
client.ip
<blockquote>
<div>Type: IP
Readable from: client, backend
The client’s IP address, either the same as <code class="docutils literal notranslate">remote.ip</code>
or what the PROXY protocol told us.
</div></blockquote>
server.hostname
<blockquote>
<div>Type: STRING
Readable from: all
The host name of the server, as returned by the
<cite>gethostname(3)</cite> system function.
</div></blockquote>
server.identity
<blockquote>
<div>Type: STRING
Readable from: all
The identity of the server, as set by the <code class="docutils literal notranslate">-i</code> parameter.
If an <code class="docutils literal notranslate">-i</code> parameter is not passed to varnishd, the return
value from <cite>gethostname(3)</cite> system function will be used.
</div></blockquote>
server.ip
<blockquote>
<div>Type: IP
Readable from: client, backend
The IP address of the socket on which the client
connection was received, either the same as <code class="docutils literal notranslate">server.ip</code>
or what the PROXY protocol told us.
</div></blockquote>
remote.ip
<blockquote>
<div>Type: IP
Readable from: client, backend
The IP address of the other end of the TCP connection.
This can either be the clients IP, or the outgoing IP
of a proxy server.
If the connection is a UNIX domain socket, the value
will be <code class="docutils literal notranslate">0.0.0.0:0</code>
</div></blockquote>
local.endpoint <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: client, backend
The address of the ‘-a’ socket the session was accepted on.
If the argument was <code class="docutils literal notranslate">-a foo=:81</code> this would be “:81”
</div></blockquote>
local.ip
<blockquote>
<div>Type: IP
Readable from: client, backend
The IP address (and port number) of the local end of the
TCP connection, for instance <code class="docutils literal notranslate">192.168.1.1:81</code>
If the connection is a UNIX domain socket, the value
will be <code class="docutils literal notranslate">0.0.0.0:0</code>
</div></blockquote>
local.socket <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: client, backend
The name of the ‘-a’ socket the session was accepted on.
If the argument was <code class="docutils literal notranslate">-a foo=:81</code> this would be “foo”.
Note that all ‘-a’ gets a default name on the form <code class="docutils literal notranslate">a%d</code>
if no name is provided.
</div></blockquote>
</section>
<section id="req-and-req-top">
<h4>req and req_top<a class="headerlink" href="#req-and-req-top" title="Link to this heading">¶</a></h4>
These variables describe the present request, and when ESI:include
requests are being processed, req_top points to the request received
from the client.
req
<blockquote>
<div>Type: HTTP
Readable from: client
The entire request HTTP data structure.
Mostly useful for passing to VMODs.
</div></blockquote>
req.backend_hint
<blockquote>
<div>Type: BACKEND
Readable from: client
Writable from: client
Set bereq.backend to this if we attempt to fetch.
When set to a director, reading this variable returns
an actual backend if the director has resolved immediately,
or the director otherwise.
When used in string context, returns the name of the director
or backend, respectively.
</div></blockquote>
req.can_gzip
<blockquote>
<div>Type: BOOL
Readable from: client
True if the client provided <code class="docutils literal notranslate">gzip</code> or <code class="docutils literal notranslate">x-gzip</code> in the
<code class="docutils literal notranslate">Accept-Encoding</code> header.
</div></blockquote>
req.esi <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: BOOL
Readable from: client
Writable from: client
Set to <code class="docutils literal notranslate">false</code> to disable ESI processing
regardless of any value in beresp.do_esi. Defaults
to <code class="docutils literal notranslate">true</code>. This variable is replaced by <code class="docutils literal notranslate">resp.do_esi</code>
in VCL 4.1.
</div></blockquote>
req.esi_level
<blockquote>
<div>Type: INT
Readable from: client
A count of how many levels of ESI requests we’re currently at.
</div></blockquote>
req.grace
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Upper limit on the object grace.
During lookup the minimum of req.grace and the object’s stored
grace value will be used as the object’s grace.
</div></blockquote>
req.hash
<blockquote>
<div>Type: BLOB
Readable from: vcl_hit, vcl_miss, vcl_pass, vcl_purge, vcl_deliver
The hash key of this request.
Mostly useful for passing to VMODs, but can also be useful
for debugging hit/miss status.
</div></blockquote>
req.hash_always_miss
<blockquote>
<div>Type: BOOL
Readable from: client
Writable from: client
Default: <code class="docutils literal notranslate">false</code>.
Force a cache miss for this request, even if perfectly
good matching objects are in the cache.
This is useful to force-update the cache without invalidating
existing entries in case the fetch fails.
</div></blockquote>
req.hash_ignore_busy
<blockquote>
<div>Type: BOOL
Readable from: client
Writable from: client
Default: <code class="docutils literal notranslate">false</code>.
Ignore any busy object during cache lookup.
You only want to do this when you have two server looking
up content sideways from each other to avoid deadlocks.
</div></blockquote>
req.hash_ignore_vary
<blockquote>
<div>Type: BOOL
Readable from: client
Writable from: client
Default: <code class="docutils literal notranslate">false</code>.
Ignore objects vary headers during cache lookup.
This returns the very first match regardless of the object
compatibility with the client request. This is useful when
variants are irrelevant to certain clients, and differences
in the way the resouce is presented don’t change how the
client will interpret it.
Use with caution.
</div></blockquote>
req.http.*
<blockquote>
<div>Type: HEADER
Readable from: client
Writable from: client
Unsetable from: client
The headers of request, things like <code class="docutils literal notranslate">req.http.date</code>.
The RFCs allow multiple headers with the same name, and both
<code class="docutils literal notranslate">set</code> and <code class="docutils literal notranslate">unset</code> will remove all headers with the name
given.
The header name <code class="docutils literal notranslate">*</code> is a VCL symbol and as such cannot, for
example, start with a numeral. To work with valid header that
can’t be represented as VCL symbols it is possible to quote the
name, like <code class="docutils literal notranslate">req.http.&quot;grammatically.valid&quot;</code>. None of the HTTP
headers present in IANA registries need to be quoted, so the
quoted syntax is discouraged but available for interoperability.
Some headers that cannot be tampered with for proper HTTP fetch
or delivery are read-only.
</div></blockquote>
req.http.content-length
<blockquote>
<div>Type: HEADER
Readable from: client
The content-length header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
req.http.transfer-encoding
<blockquote>
<div>Type: HEADER
Readable from: client
The transfer-encoding header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
req.is_hitmiss
<blockquote>
<div>Type: BOOL
Readable from: client
If this request resulted in a hitmiss
</div></blockquote>
req.is_hitpass
<blockquote>
<div>Type: BOOL
Readable from: client
If this request resulted in a hitpass
</div></blockquote>
req.method
<blockquote>
<div>Type: STRING
Readable from: client
Writable from: client
The request method (e.g. “GET”, “HEAD”, …)
</div></blockquote>
req.proto <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: STRING
Readable from: client
Writable from: client
The HTTP protocol version used by the client, usually “HTTP/1.1”
or “HTTP/2.0”.
</div></blockquote>
req.proto <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: client
The HTTP protocol version used by the client, usually “HTTP/1.1”
or “HTTP/2.0”.
</div></blockquote>
req.restarts
<blockquote>
<div>Type: INT
Readable from: client
A count of how many times this request has been restarted.
</div></blockquote>
req.storage
<blockquote>
<div>Type: STEVEDORE
Readable from: client
Writable from: client
The storage backend to use to save this request body.
</div></blockquote>
req.time
<blockquote>
<div>Type: TIME
Readable from: client
The time when the request was fully received, remains constant
across restarts.
</div></blockquote>
req.trace
<blockquote>
<div>Type: BOOL
Readable from: client
Writable from: client
Controls if <code class="docutils literal notranslate">VCL_trace</code> VSL records are emitted for the current
request, see <a class="reference internal" href="vsl.html#vsl-7">VSL</a>.
Defaults to the setting of the <code class="docutils literal notranslate">feature trace</code> parameter,
see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>. Does not get reset by a rollback.
</div></blockquote>
req.transport
<blockquote>
<div>Type: STRING
Readable from: client
The transport protocol which brought this request.
</div></blockquote>
req.ttl
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Upper limit on the object age for cache lookups to return hit.
</div></blockquote>
req.url
<blockquote>
<div>Type: STRING
Readable from: client
Writable from: client
The requested URL, for instance “/robots.txt”.
</div></blockquote>
req.xid
<blockquote>
<div>Type: INT
Readable from: client
Unique ID of this request.
</div></blockquote>
req_top.http.*
<blockquote>
<div>Type: HEADER
Readable from: client
HTTP headers of the top-level request in a tree of ESI requests.
Identical to req.http. in non-ESI requests.
See <a class="reference internal" href="#req-http">req.http</a> for general notes.
</div></blockquote>
req_top.method
<blockquote>
<div>Type: STRING
Readable from: client
The request method of the top-level request in a tree
of ESI requests. (e.g. “GET”, “HEAD”).
Identical to req.method in non-ESI requests.
</div></blockquote>
req_top.proto
<blockquote>
<div>Type: STRING
Readable from: client
HTTP protocol version of the top-level request in a tree of
ESI requests.
Identical to req.proto in non-ESI requests.
</div></blockquote>
req_top.time
<blockquote>
<div>Type: TIME
Readable from: client
The time when the top-level request was fully received,
remains constant across restarts.
</div></blockquote>
req_top.url
<blockquote>
<div>Type: STRING
Readable from: client
The requested URL of the top-level request in a tree
of ESI requests.
Identical to req.url in non-ESI requests.
</div></blockquote>
</section>
<section id="bereq">
<h4>bereq<a class="headerlink" href="#bereq" title="Link to this heading">¶</a></h4>
This is the request we send to the backend, it is built from the
clients <code class="docutils literal notranslate">req.*</code> fields by filtering out “per-hop” fields which
should not be passed along (<code class="docutils literal notranslate">Connection:</code>, <code class="docutils literal notranslate">Range:</code> and similar).
Slightly more fields are allowed through for <code class="docutils literal notranslate">pass` fetches
than for `miss` fetches, for instance ``Range</code>.
bereq
<blockquote>
<div>Type: HTTP
Readable from: backend
The entire backend request HTTP data structure.
Mostly useful as argument to VMODs.
</div></blockquote>
bereq.backend
<blockquote>
<div>Type: BACKEND
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
This is the backend or director we attempt to fetch from.
When set to a director, reading this variable returns
an actual backend if the director has resolved immediately,
or the director otherwise.
When used in string context, returns the name of the director
or backend, respectively.
</div></blockquote>
bereq.between_bytes_timeout
<blockquote>
<div>Type: DURATION
Readable from: backend
Writable from: backend
Unsetable from: vcl_pipe, backend
Default: <code class="docutils literal notranslate">.between_bytes_timeout</code> attribute from the
<a class="reference internal" href="vcl-backend.html#backend-definition">Backend definition</a>, which defaults to the
<code class="docutils literal notranslate">between_bytes_timeout</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>.
The time in seconds to wait between each received byte from the
backend. Not available in pipe mode.
</div></blockquote>
bereq.body
<blockquote>
<div>Type: BODY
Unsetable from: vcl_backend_fetch
The request body.
Unset will also remove <a class="reference internal" href="#bereq-http-content-length">bereq.http.content-length</a>.
</div></blockquote>
bereq.connect_timeout
<blockquote>
<div>Type: DURATION
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
Unsetable from: vcl_pipe, backend
Default: <code class="docutils literal notranslate">.connect_timeout</code> attribute from the
<a class="reference internal" href="vcl-backend.html#backend-definition">Backend definition</a>, which defaults to the
<code class="docutils literal notranslate">connect_timeout</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>.
The time in seconds to wait for a backend connection to be
established.
</div></blockquote>
bereq.first_byte_timeout
<blockquote>
<div>Type: DURATION
Readable from: backend
Writable from: backend
Unsetable from: vcl_pipe, backend
Default: <code class="docutils literal notranslate">.first_byte_timeout</code> attribute from the
<a class="reference internal" href="vcl-backend.html#backend-definition">Backend definition</a>, which defaults to the
<code class="docutils literal notranslate">first_byte_timeout</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>.
The time in seconds to wait getting the first byte back
from the backend. Not available in pipe mode.
</div></blockquote>
bereq.hash
<blockquote>
<div>Type: BLOB
Readable from: vcl_pipe, backend
The hash key of this request, a copy of <code class="docutils literal notranslate">req.hash</code>.
</div></blockquote>
bereq.http.*
<blockquote>
<div>Type: HEADER
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
Unsetable from: vcl_pipe, backend
The headers to be sent to the backend.
See <a class="reference internal" href="#req-http">req.http</a> for general notes.
</div></blockquote>
bereq.http.content-length
<blockquote>
<div>Type: HEADER
Readable from: backend
The content-length header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
bereq.http.transfer-encoding
<blockquote>
<div>Type: HEADER
Readable from: backend
The transfer-encoding header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
bereq.is_bgfetch
<blockquote>
<div>Type: BOOL
Readable from: backend
True for fetches where the client got a hit on an object in
grace, and this fetch was kicked of in the background to get
a fresh copy.
</div></blockquote>
bereq.is_hitmiss
<blockquote>
<div>Type: BOOL
Readable from: backend
If this backend request was caused by a hitmiss.
</div></blockquote>
bereq.is_hitpass
<blockquote>
<div>Type: BOOL
Readable from: backend
If this backend request was caused by a hitpass.
</div></blockquote>
bereq.method
<blockquote>
<div>Type: STRING
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
The request type (e.g. “GET”, “HEAD”).
Regular (non-pipe, non-pass) fetches are always “GET”
</div></blockquote>
bereq.proto <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
The HTTP protocol version, “HTTP/1.1” unless a pass or pipe
request has “HTTP/1.0” in <code class="docutils literal notranslate">req.proto</code>
</div></blockquote>
bereq.proto <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_pipe, backend
The HTTP protocol version, “HTTP/1.1” unless a pass or pipe
request has “HTTP/1.0” in <code class="docutils literal notranslate">req.proto</code>
</div></blockquote>
bereq.retries
<blockquote>
<div>Type: INT
Readable from: backend
A count of how many times this request has been retried.
</div></blockquote>
bereq.task_deadline
<blockquote>
<div>Type: DURATION
Readable from: vcl_pipe
Writable from: vcl_pipe
Unsetable from: vcl_pipe
Deadline for pipe sessions, defaults <code class="docutils literal notranslate">0s</code>, which falls back to the
<code class="docutils literal notranslate">pipe_task_deadline</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>
</div></blockquote>
bereq.time
<blockquote>
<div>Type: TIME
Readable from: vcl_pipe, backend
The time when we started preparing the first backend request,
remains constant across retries.
</div></blockquote>
bereq.trace
<blockquote>
<div>Type: BOOL
Readable from: backend
Writable from: backend
Controls if <code class="docutils literal notranslate">VCL_trace</code> VSL records are emitted for the current
request, see <a class="reference internal" href="vsl.html#vsl-7">VSL</a>.
Inherits the value of <code class="docutils literal notranslate">req.trace</code> when the backend request
is created. Does not get reset by a rollback.
</div></blockquote>
bereq.uncacheable
<blockquote>
<div>Type: BOOL
Readable from: backend
Indicates whether this request is uncacheable due to a
<cite>pass</cite> in the client side or a hit on an hit-for-pass object.
</div></blockquote>
bereq.url
<blockquote>
<div>Type: STRING
Readable from: vcl_pipe, backend
Writable from: vcl_pipe, backend
The requested URL, copied from <code class="docutils literal notranslate">req.url</code>
</div></blockquote>
bereq.xid
<blockquote>
<div>Type: INT
Readable from: vcl_pipe, backend
Unique ID of this request.
</div></blockquote>
</section>
<section id="beresp">
<h4>beresp<a class="headerlink" href="#beresp" title="Link to this heading">¶</a></h4>
The response received from the backend, one cache misses, the
store object is built from <code class="docutils literal notranslate">beresp</code>.
beresp
<blockquote>
<div>Type: HTTP
Readable from: vcl_backend_response, vcl_backend_error
The entire backend response HTTP data structure, useful as
argument to VMOD functions.
</div></blockquote>
beresp.age
<blockquote>
<div>Type: DURATION
Readable from: vcl_backend_response, vcl_backend_error
Default: Age header, or zero.
The age of the object.
</div></blockquote>
beresp.backend
<blockquote>
<div>Type: BACKEND
Readable from: vcl_backend_response, vcl_backend_error
This is the backend we fetched from. If bereq.backend
was set to a director, this will be the backend selected
by the director.
When used in string context, returns its name.
</div></blockquote>
beresp.backend.ip <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: IP
Readable from: vcl_backend_response
IP of the backend this response was fetched from.
</div></blockquote>
beresp.backend.name
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response, vcl_backend_error
Name of the backend this response was fetched from.
Same as beresp.backend.
</div></blockquote>
beresp.body
<blockquote>
<div>Type: BODY
Writable from: vcl_backend_error
For producing a synthetic body.
</div></blockquote>
beresp.do_esi
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: <code class="docutils literal notranslate">false</code>.
Set it to true to parse the object for ESI directives. This is
necessary for later ESI processing on the client side. If
beresp.do_esi is false when an object enters the cache, client
side ESI processing will not be possible (obj.can_esi will be
false).
It is a VCL error to use beresp.do_esi after setting beresp.filters.
</div></blockquote>
beresp.do_gunzip
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: <code class="docutils literal notranslate">false</code>.
Set to <code class="docutils literal notranslate">true</code> to gunzip the object while storing it in the
cache.
If <code class="docutils literal notranslate">http_gzip_support</code> is disabled, setting this variable
has no effect.
It is a VCL error to use beresp.do_gunzip after setting beresp.filters.
</div></blockquote>
beresp.do_gzip
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: <code class="docutils literal notranslate">false</code>.
Set to <code class="docutils literal notranslate">true</code> to gzip the object while storing it.
If <code class="docutils literal notranslate">http_gzip_support</code> is disabled, setting this variable
has no effect.
It is a VCL error to use beresp.do_gzip after setting beresp.filters.
</div></blockquote>
beresp.do_stream
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: <code class="docutils literal notranslate">true</code>.
Deliver the object to the client while fetching the whole
object into varnish.
For uncacheable objects, storage for parts of the body which
have been sent to the client may get freed early, depending
on the storage engine used.
This variable has no effect if beresp.do_esi is true or when
the response body is empty.
</div></blockquote>
beresp.filters
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response
Writable from: vcl_backend_response
List of Varnish Fetch Processor (VFP) filters the beresp.body
will be pulled through. The order left to right signifies
processing from backend to cache, iow the leftmost filter is
run first on the body as received from the backend after
decoding of any transfer encodings.
VFP Filters change the body before going into the cache and/or
being handed to the client side, where it may get processed
again by resp.filters.
The following VFP filters exist in varnish-cache:
<ul>
<li><code class="docutils literal notranslate">gzip</code>: compress a body using gzip</li>
<li><code class="docutils literal notranslate">testgunzip</code>: Test if a body is valid gzip and refuse it
otherwise</li>
<li><code class="docutils literal notranslate">gunzip</code>: Uncompress gzip content</li>
<li><code class="docutils literal notranslate">esi</code>: ESI-process plain text content</li>
<li><code class="docutils literal notranslate">esi_gzip</code>: Save gzipped snippets for efficient
ESI-processing
This filter enables stitching together ESI from individually
gzipped fragments, saving processing power for
re-compression on the client side at the expense of some
compression efficiency.
</li>
</ul>
Additional VFP filters are available from VMODs.
By default, beresp.filters is constructed as follows:
<ul class="simple">
<li><code class="docutils literal notranslate">gunzip</code> gets added for gzipped content if
<code class="docutils literal notranslate">beresp.do_gunzip</code> or <code class="docutils literal notranslate">beresp.do_esi</code> are true.</li>
<li><code class="docutils literal notranslate">esi_gzip</code> gets added if <code class="docutils literal notranslate">beresp.do_esi</code> is true
together with <code class="docutils literal notranslate">beresp.do_gzip</code> or content is already
compressed.</li>
<li><code class="docutils literal notranslate">esi</code> gets added if <code class="docutils literal notranslate">beresp.do_esi</code> is true</li>
<li><code class="docutils literal notranslate">gzip</code> gets added for uncompressed content if
<code class="docutils literal notranslate">beresp.do_gzip</code> is true</li>
<li><code class="docutils literal notranslate">testgunzip</code> gets added for compressed content if
<code class="docutils literal notranslate">beresp.do_gunzip</code> is false.</li>
</ul>
After beresp.filters is set, using any of the beforementioned
<code class="docutils literal notranslate">beresp.do_*</code> switches is a VCL error.
</div></blockquote>
beresp.grace
<blockquote>
<div>Type: DURATION
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: Cache-Control <code class="docutils literal notranslate">stale-while-revalidate</code> directive,
or <code class="docutils literal notranslate">default_grace</code> parameter.
Set to a period to enable grace.
</div></blockquote>
beresp.http.*
<blockquote>
<div>Type: HEADER
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Unsetable from: vcl_backend_response, vcl_backend_error
The HTTP headers returned from the server.
See <a class="reference internal" href="#req-http">req.http</a> for general notes.
</div></blockquote>
beresp.http.content-length
<blockquote>
<div>Type: HEADER
Readable from: vcl_backend_response, vcl_backend_error
The content-length header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
beresp.http.transfer-encoding
<blockquote>
<div>Type: HEADER
Readable from: vcl_backend_response, vcl_backend_error
The transfer-encoding header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
beresp.keep
<blockquote>
<div>Type: DURATION
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: <code class="docutils literal notranslate">default_keep</code> parameter.
Set to a period to enable conditional backend requests.
The keep time is cache lifetime in addition to the ttl.
Objects with ttl expired but with keep time left may be used
to issue conditional (If-Modified-Since / If-None-Match)
requests to the backend to refresh them.
</div></blockquote>
beresp.proto <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
The HTTP protocol version the backend replied with.
</div></blockquote>
beresp.proto <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response, vcl_backend_error
The HTTP protocol version the backend replied with.
</div></blockquote>
beresp.reason
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
The HTTP status message returned by the server.
</div></blockquote>
beresp.status
<blockquote>
<div>Type: INT
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
The HTTP status code returned by the server.
More information in the <a class="reference internal" href="#http-response-status">HTTP response status</a> section.
</div></blockquote>
beresp.storage
<blockquote>
<div>Type: STEVEDORE
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
The storage backend to use to save this object.
</div></blockquote>
beresp.storage_hint <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Deprecated since varnish 5.1 and discontinued since VCL
4.1 (varnish 6.0). Use beresp.storage instead.
Hint to Varnish that you want to save this object to a
particular storage backend.
</div></blockquote>
beresp.time
<blockquote>
<div>Type: TIME
Readable from: vcl_backend_response, vcl_backend_error
When the backend headers were fully received just before
<code class="docutils literal notranslate">vcl_backend_response {}</code> was entered, or when
<code class="docutils literal notranslate">vcl_backend_error {}</code> was entered.
</div></blockquote>
beresp.transit_buffer
<blockquote>
<div>Type: BYTES
Readable from: vcl_backend_response
Writable from: vcl_backend_response
Default: <code class="docutils literal notranslate">transit_buffer</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>.
The maximum number of bytes the client can be ahead of the
backend during a streaming pass if <code class="docutils literal notranslate">beresp</code> is
uncacheable. See also <code class="docutils literal notranslate">transit_buffer</code> parameter
documentation in <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>.
</div></blockquote>
beresp.ttl
<blockquote>
<div>Type: DURATION
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Default: Cache-Control <code class="docutils literal notranslate">s-maxage</code> or <code class="docutils literal notranslate">max-age</code> directives,
or a value computed from the Expires header’s deadline, or the
<code class="docutils literal notranslate">default_ttl</code> parameter.
The object’s remaining time to live, in seconds.
</div></blockquote>
beresp.uncacheable
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
Writable from: vcl_backend_response, vcl_backend_error
Inherited from bereq.uncacheable, see there.
Setting this variable makes the object uncacheable.
This may may produce a hit-for-miss object in the cache.
Clearing the variable has no effect and will log the warning
“Ignoring attempt to reset beresp.uncacheable”.
</div></blockquote>
beresp.was_304
<blockquote>
<div>Type: BOOL
Readable from: vcl_backend_response, vcl_backend_error
When <code class="docutils literal notranslate">true</code> this indicates that we got a 304 response
to our conditional fetch from the backend and turned
that into <code class="docutils literal notranslate">beresp.status = 200</code>
</div></blockquote>
</section>
<section id="obj">
<h4>obj<a class="headerlink" href="#obj" title="Link to this heading">¶</a></h4>
This is the object we found in cache. It cannot be modified.
obj.age
<blockquote>
<div>Type: DURATION
Readable from: vcl_hit, vcl_deliver
The age of the object.
</div></blockquote>
obj.can_esi
<blockquote>
<div>Type: BOOL
Readable from: vcl_hit, vcl_deliver
If the object can be ESI processed, that is if setting
<code class="docutils literal notranslate">resp.do_esi</code> or adding <code class="docutils literal notranslate">esi</code> to <code class="docutils literal notranslate">resp.filters</code> in
<code class="docutils literal notranslate">vcl_deliver {}</code> would cause the response body to be ESI
processed.
</div></blockquote>
obj.grace
<blockquote>
<div>Type: DURATION
Readable from: vcl_hit, vcl_deliver
The object’s grace period in seconds.
</div></blockquote>
obj.hits
<blockquote>
<div>Type: INT
Readable from: vcl_hit, vcl_deliver
The count of cache-hits on this object.
In <cite>vcl_deliver</cite> a value of 0 indicates a cache miss.
</div></blockquote>
obj.http.*
<blockquote>
<div>Type: HEADER
Readable from: vcl_hit
The HTTP headers stored in the object.
See <a class="reference internal" href="#req-http">req.http</a> for general notes.
</div></blockquote>
obj.keep
<blockquote>
<div>Type: DURATION
Readable from: vcl_hit, vcl_deliver
The object’s keep period in seconds.
</div></blockquote>
obj.proto
<blockquote>
<div>Type: STRING
Readable from: vcl_hit
The HTTP protocol version stored in the object.
</div></blockquote>
obj.reason
<blockquote>
<div>Type: STRING
Readable from: vcl_hit
The HTTP reason phrase stored in the object.
</div></blockquote>
obj.status
<blockquote>
<div>Type: INT
Readable from: vcl_hit
The HTTP status code stored in the object.
More information in the <a class="reference internal" href="#http-response-status">HTTP response status</a> section.
</div></blockquote>
obj.storage
<blockquote>
<div>Type: STEVEDORE
Readable from: vcl_hit, vcl_deliver
The storage backend where this object is stored.
</div></blockquote>
obj.time
<blockquote>
<div>Type: TIME
Readable from: vcl_hit, vcl_deliver
The time the object was created from the perspective of the
server which generated it. This will roughly be equivalent to
<code class="docutils literal notranslate">now</code> - <code class="docutils literal notranslate">obj.age</code>.
</div></blockquote>
obj.ttl
<blockquote>
<div>Type: DURATION
Readable from: vcl_hit, vcl_deliver
The object’s remaining time to live, in seconds.
</div></blockquote>
obj.uncacheable
<blockquote>
<div>Type: BOOL
Readable from: vcl_deliver
Whether the object is uncacheable (pass, hit-for-pass or
hit-for-miss).
</div></blockquote>
</section>
<section id="resp">
<h4>resp<a class="headerlink" href="#resp" title="Link to this heading">¶</a></h4>
This is the response we send to the client, it is built from either
<code class="docutils literal notranslate">beresp</code> (pass/miss), <code class="docutils literal notranslate">obj</code> (hits) or created from whole cloth (synth).
With the exception of <code class="docutils literal notranslate">resp.body</code> all <code class="docutils literal notranslate">resp.*</code> variables available
in both <code class="docutils literal notranslate">vcl_deliver{}</code> and <code class="docutils literal notranslate">vcl_synth{}</code> as a matter of symmetry.
resp
<blockquote>
<div>Type: HTTP
Readable from: vcl_deliver, vcl_synth
The entire response HTTP data structure, useful as argument
to VMODs.
</div></blockquote>
resp.body
<blockquote>
<div>Type: BODY
Writable from: vcl_synth
To produce a synthetic response body, for instance for errors.
</div></blockquote>
resp.do_esi <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: BOOL
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
Default: obj.can_esi
This can be used to selectively disable ESI processing, even
though ESI parsing happened during fetch (see beresp.do_esi).
This is useful when Varnish caches peer with each other.
It is a VCL error to use resp.do_esi after setting resp.filters.
</div></blockquote>
resp.filters
<blockquote>
<div>Type: STRING
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
List of VDP filters the resp.body will be pushed through.
Before resp.filters is set, the value read will be the default
filter list as determined by varnish based on resp.do_esi and
request headers.
After resp.filters is set, changing any of the conditions
which otherwise determine the filter selection will have no
effiect. Using resp.do_esi is an error once resp.filters is
set.
</div></blockquote>
resp.http.*
<blockquote>
<div>Type: HEADER
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
Unsetable from: vcl_deliver, vcl_synth
The HTTP headers that will be returned.
See <a class="reference internal" href="#req-http">req.http</a> for general notes.
</div></blockquote>
resp.http.content-length
<blockquote>
<div>Type: HEADER
Readable from: vcl_deliver, vcl_synth
The content-length header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
resp.http.transfer-encoding
<blockquote>
<div>Type: HEADER
Readable from: vcl_deliver, vcl_synth
The transfer-encoding header field is protected, see <a class="reference internal" href="#protected-headers">protected_headers</a>.
</div></blockquote>
resp.is_streaming
<blockquote>
<div>Type: BOOL
Readable from: vcl_deliver, vcl_synth
Returns true when the response will be streamed
while being fetched from the backend.
</div></blockquote>
resp.proto <code class="docutils literal notranslate">VCL &lt;= 4.0</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
The HTTP protocol version to use for the response.
</div></blockquote>
resp.proto <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: STRING
Readable from: vcl_deliver, vcl_synth
The HTTP protocol version to use for the response.
</div></blockquote>
resp.reason
<blockquote>
<div>Type: STRING
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
The HTTP status message that will be returned.
</div></blockquote>
resp.status
<blockquote>
<div>Type: INT
Readable from: vcl_deliver, vcl_synth
Writable from: vcl_deliver, vcl_synth
The HTTP status code that will be returned.
More information in the <a class="reference internal" href="#http-response-status">HTTP response status</a> section.
resp.status 200 will get changed into 304 by core code after
a return(deliver) from vcl_deliver for conditional requests
to cached content if validation succeeds.
For the validation, first <code class="docutils literal notranslate">req.http.If-None-Match</code> is
compared against <code class="docutils literal notranslate">resp.http.Etag</code>. If they compare equal
according to the rules for weak validation (see RFC7232), a
304 is sent.
Secondly, <code class="docutils literal notranslate">req.http.If-Modified-Since</code> is compared against
<code class="docutils literal notranslate">resp.http.Last-Modified</code> or, if it is unset or weak, against
the point in time when the object was last modified based on the
<code class="docutils literal notranslate">Date</code> and <code class="docutils literal notranslate">Age</code> headers received with the backend
response which created the object. If the object has not been
modified based on that comparison, a 304 is sent.
</div></blockquote>
resp.time
<blockquote>
<div>Type: TIME
Readable from: vcl_deliver, vcl_synth
The time when we started preparing the response, just before
entering <code class="docutils literal notranslate">vcl_synth {}</code> or <code class="docutils literal notranslate">vcl_deliver {}</code>.
</div></blockquote>
</section>
<section id="special-variables">
<h4>Special variables<a class="headerlink" href="#special-variables" title="Link to this heading">¶</a></h4>
now
<blockquote>
<div>Type: TIME
Readable from: all
The current time, in seconds since the UNIX epoch.
When converted to STRING in expressions it returns
a formatted timestamp like <code class="docutils literal notranslate">Tue, 20 Feb 2018 09:30:31 GMT</code>
<code class="docutils literal notranslate">now</code> remains stable for the duration of any built-in VCL
subroutine to make time-based calculations predictable and
avoid edge cases.
In other words, even if considerable amounts of time are spent
in VCL, <code class="docutils literal notranslate">now</code> will always represent the point in time when
the respective built-in VCL subroutine was entered. <code class="docutils literal notranslate">now</code> is
thus not suitable for any kind of time measurements. See
<a class="reference internal" href="vmod_std.html#std-timestamp">VOID timestamp(STRING s)</a>, <a class="reference internal" href="vmod_std.html#std-now">TIME now()</a> and
<a class="reference internal" href="vmod_std.html#std-timed-call">DURATION timed_call(SUB)</a> in <a class="reference internal" href="vmod_std.html#vmod-std-3">VMOD std - Varnish Standard Module</a>.
</div></blockquote>
</section>
<section id="sess">
<h4>sess<a class="headerlink" href="#sess" title="Link to this heading">¶</a></h4>
A session corresponds to the “conversation” that Varnish has with a
single client connection, over which one or more request/response
transactions may take place. It may comprise the traffic over an
HTTP/1 keep-alive connection, or the multiplexed traffic over an
HTTP/2 connection.
sess.idle_send_timeout
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Unsetable from: client
Send timeout for individual pieces of data on client
connections, defaults to the <code class="docutils literal notranslate">idle_send_timeout</code> parameter,
see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>
</div></blockquote>
sess.send_timeout
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Unsetable from: client
Total timeout for ordinary HTTP1 responses, defaults to the
<code class="docutils literal notranslate">send_timeout</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>
</div></blockquote>
sess.timeout_idle
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Unsetable from: client
Idle timeout for this session, defaults to the
<code class="docutils literal notranslate">timeout_idle</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>
</div></blockquote>
sess.timeout_linger
<blockquote>
<div>Type: DURATION
Readable from: client
Writable from: client
Unsetable from: client
Linger timeout for this session, defaults to the
<code class="docutils literal notranslate">timeout_linger</code> parameter, see <a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a>
</div></blockquote>
sess.xid <code class="docutils literal notranslate">VCL &gt;= 4.1</code>
<blockquote>
<div>Type: INT
Readable from: client, backend
Unique ID of this session.
</div></blockquote>
</section>
<section id="storage">
<h4>storage<a class="headerlink" href="#storage" title="Link to this heading">¶</a></h4>
storage.&lt;name&gt;.free_space
<blockquote>
<div>Type: BYTES
Readable from: client, backend
Default: 0
Free space available in the named stevedore. Only available for
the malloc stevedore.
</div></blockquote>
storage.&lt;name&gt;.happy
<blockquote>
<div>Type: BOOL
Readable from: client, backend
Default: true
Health status for the named stevedore. Not available in any of the
current stevedores.
</div></blockquote>
storage.&lt;name&gt;.used_space
<blockquote>
<div>Type: BYTES
Readable from: client, backend
Default: 0
Used space in the named stevedore. Only available for the malloc
stevedore.
</div></blockquote>
</section>
<section id="protected-header-fields">
<h4>Protected header fields<a class="headerlink" href="#protected-header-fields" title="Link to this heading">¶</a></h4>
The <code class="docutils literal notranslate">content-length</code> and <code class="docutils literal notranslate">transfer-encoding</code> headers are read-only. They
must be preserved to ensure HTTP/1 framing remains consistent and maintain a
proper request and response synchronization with both clients and backends.
VMODs can still update these headers, when there is a reason to change the
framing, such as a transformation of a request or response body.
</section>
<section id="http-response-status">
<h4>HTTP response status<a class="headerlink" href="#http-response-status" title="Link to this heading">¶</a></h4>
A HTTP status code has 3 digits XYZ where X must be between 1 and 5 included.
Since it is not uncommon to see HTTP clients or servers relying
on non-standard or even invalid status codes, Varnish can work
with any status between 100 and 999.
Within VCL code it is even possible to use status codes in the form
VWXYZ as long as the overall value is lower than 65536, but only
the XYZ part will be sent to the client, by which time the X must
also have become non-zero.
The VWXYZ form of status codes can be communicate extra information
in <code class="docutils literal notranslate">resp.status</code> and <code class="docutils literal notranslate">beresp.status</code> to <code class="docutils literal notranslate">return(synth(...))</code> and
<code class="docutils literal notranslate">return(error(...))</code>, to indicate which synthetic content to produce:
<div class="highlight-default notranslate"><div class="highlight"><pre>sub vcl_recv {
 if ([...]) {
 return synth(12404);
 }
}

sub vcl_synth {
 if (resp.status == 12404) {
 [...] // this specific 404
 } else if (resp.status % 1000 == 404) {
 [...] // all other 404&#39;s
 }
}
</pre></div>
</div>
The <code class="docutils literal notranslate">obj.status</code> variable will inherit the VWXYZ form, but in a ban
expression only the XYZ part will be available. The VWXYZ form is strictly
limited to VCL execution.
Assigning an HTTP standardized code to <code class="docutils literal notranslate">resp.status</code> or <code class="docutils literal notranslate">beresp.status</code>
will also set <code class="docutils literal notranslate">resp.reason</code> or <code class="docutils literal notranslate">beresp.reason</code> to the corresponding
status message.
<section id="handling">
<h5>304 handling<a class="headerlink" href="#handling" title="Link to this heading">¶</a></h5>
For a 304 response, Varnish core code amends <code class="docutils literal notranslate">beresp</code> before calling
<cite>vcl_backend_response</cite>:
<ul class="simple">
<li>If the gzip status changed, <code class="docutils literal notranslate">Content-Encoding</code> is unset and any
<code class="docutils literal notranslate">Etag</code> is weakened</li>
<li>Any headers not present in the 304 response are copied from the
existing cache object. <code class="docutils literal notranslate">Content-Length</code> is copied if present in
the existing cache object and discarded otherwise.</li>
<li>The status gets set to 200.</li>
</ul>
<cite>beresp.was_304</cite> marks that this conditional response processing has
happened.
Note: Backend conditional requests are independent of client
conditional requests, so clients may receive 304 responses no matter
if a backend request was conditional.
</section>
<section id="beresp-ttl-beresp-grace-beresp-keep">
<h5>beresp.ttl / beresp.grace / beresp.keep<a class="headerlink" href="#beresp-ttl-beresp-grace-beresp-keep" title="Link to this heading">¶</a></h5>
Before calling <cite>vcl_backend_response</cite>, core code sets <code class="docutils literal notranslate">beresp.ttl</code>
based on the response status and the response headers <code class="docutils literal notranslate">Age</code>,
<code class="docutils literal notranslate">Cache-Control</code> or <code class="docutils literal notranslate">Expires</code> and <code class="docutils literal notranslate">Date</code> as follows:
<ul class="simple">
<li>If present and valid, the value of the <code class="docutils literal notranslate">Age</code> header is effectively
deduced from all ttl calculations.</li>
<li>For status codes 200, 203, 204, 300, 301, 304, 404, 410 and 414:
<ul>
<li>If <code class="docutils literal notranslate">Cache-Control</code> contains an <code class="docutils literal notranslate">s-maxage</code> or <code class="docutils literal notranslate">max-age</code> field
(in that order of preference), the ttl is set to the respective
non-negative value or 0 if negative.</li>
<li>Otherwise, if no <code class="docutils literal notranslate">Expires</code> header exists, the default ttl is
used.</li>
<li>Otherwise, if <code class="docutils literal notranslate">Expires</code> contains a time stamp before <code class="docutils literal notranslate">Date</code>,
the ttl is set to 0.</li>
<li>Otherwise, if no <code class="docutils literal notranslate">Date</code> header is present or the <code class="docutils literal notranslate">Date</code> header
timestamp differs from the local clock by no more than the
<cite>clock_skew</cite> parameter, the ttl is set to
<ul>
<li>0 if <code class="docutils literal notranslate">Expires</code> denotes a past timestamp or</li>
<li>the difference between the local clock and the <code class="docutils literal notranslate">Expires</code>
header otherwise.</li>
</ul>
</li>
<li>Otherwise, the ttl is set to the difference between <code class="docutils literal notranslate">Expires</code>
and <code class="docutils literal notranslate">Date</code></li>
</ul>
</li>
<li>For status codes 302 and 307, the calculation is identical except
that the default ttl is not used and -1 is returned if neither
<code class="docutils literal notranslate">Cache-Control</code> nor <code class="docutils literal notranslate">Expires</code> exists.</li>
<li>For all other status codes, ttl -1 is returned.</li>
</ul>
<code class="docutils literal notranslate">beresp.grace</code> defaults to the <cite>default_grace</cite> parameter.
For a non-negative ttl, if <code class="docutils literal notranslate">Cache-Control</code> contains a
<code class="docutils literal notranslate">stale-while-revalidate</code> field value, <code class="docutils literal notranslate">beresp.grace</code> is
set to that value if non-negative or 0 otherwise.
<code class="docutils literal notranslate">beresp.keep</code> defaults to the <cite>default_keep</cite> parameter.
</section>
</section>
</section>
<section id="see-also">
<h3>SEE ALSO<a class="headerlink" href="#see-also" title="Link to this heading">¶</a></h3>
<ul class="simple">
<li><a class="reference internal" href="varnishd.html#varnishd-1">varnishd</a></li>
<li><a class="reference internal" href="vcl.html#vcl-7">VCL</a></li>
</ul>
</section>
<section id="history">
<h3>HISTORY<a class="headerlink" href="#history" title="Link to this heading">¶</a></h3>
VCL was developed by Poul-Henning Kamp in cooperation with Verdens
Gang AS, Redpill Linpro and Varnish Software. This manual page is
written by Per Buer, Poul-Henning Kamp, Martin Blix Grydeland,
Kristian Lyngstøl, Lasse Karstensen and others.
</section>
<section id="copyright">
<h3>COPYRIGHT<a class="headerlink" href="#copyright" title="Link to this heading">¶</a></h3>
This document is licensed under the same license as Varnish
itself. See LICENSE for details.
<ul class="simple">
<li>Copyright (c) 2006 Verdens Gang AS</li>
<li>Copyright (c) 2006-2021 Varnish Software AS</li>
</ul>
</section>
</section>
</section>

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 <h3><a href="../index.html">Table of Contents</a></h3>
 <ul>
<li><a class="reference internal" href="#">VCL-Variables</a><ul>
<li><a class="reference internal" href="#the-complete-album">The complete album</a><ul>
<li><a class="reference internal" href="#description">DESCRIPTION</a><ul>
<li><a class="reference internal" href="#local-server-remote-and-client">local, server, remote and client</a></li>
<li><a class="reference internal" href="#req-and-req-top">req and req_top</a></li>
<li><a class="reference internal" href="#bereq">bereq</a></li>
<li><a class="reference internal" href="#beresp">beresp</a></li>
<li><a class="reference internal" href="#obj">obj</a></li>
<li><a class="reference internal" href="#resp">resp</a></li>
<li><a class="reference internal" href="#special-variables">Special variables</a></li>
<li><a class="reference internal" href="#sess">sess</a></li>
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<li><a class="reference internal" href="#http-response-status">HTTP response status</a><ul>
<li><a class="reference internal" href="#handling">304 handling</a></li>
<li><a class="reference internal" href="#beresp-ttl-beresp-grace-beresp-keep">beresp.ttl / beresp.grace / beresp.keep</a></li>
</ul>
</li>
</ul>
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<li><a class="reference internal" href="#see-also">SEE ALSO</a></li>
<li><a class="reference internal" href="#history">HISTORY</a></li>
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