.. role:: ref(emphasis)
.. _varnishd(1):
========
varnishd
========
-----------------------
HTTP accelerator daemon
-----------------------
:Manual section: 1
SYNOPSIS
========
varnishd [-a address[:port][,PROTO]] [-b host[:port]] [-C] [-d] [-F] [-f config] [-h type[,options]] [-i identity] [-j jail[,jailoptions]] [-l vsl[,vsm]] [-M address:port] [-n name] [-P file] [-p param=value] [-r param[,param...]] [-S secret-file] [-s [name=]kind[,options]] [-T address[:port]] [-t TTL] [-V] [-W waiter]
DESCRIPTION
===========
The `varnishd` daemon accepts HTTP requests from clients, passes them on
to a backend server and caches the returned documents to better
satisfy future requests for the same document.
.. _ref-varnishd-options:
OPTIONS
=======
-a
Listen for client requests on the specified address and port. The
address can be a host name ("localhost"), an IPv4 dotted-quad
("127.0.0.1"), or an IPv6 address enclosed in square brackets
("[::1]"). If address is not specified, `varnishd` will listen on all
available IPv4 and IPv6 interfaces. If port is not specified, port
80 (http) is used.
An additional protocol type can be set for the listening socket with PROTO.
Valid protocol types are: HTTP/1 (default), and PROXY.
Multiple listening addresses can be specified by using multiple -a arguments.
-b
Use the specified host as backend server. If port is not specified,
the default is 8080.
-C
Print VCL code compiled to C language and exit. Specify the VCL file
to compile with the -f option.
-d
Enables debugging mode: The parent process runs in the foreground
with a CLI connection on stdin/stdout, and the child process must be
started explicitly with a CLI command. Terminating the parent
process will also terminate the child.
-F
Do not fork, run in the foreground.
-f config
Use the specified VCL configuration file instead of the builtin
default. See :ref:`vcl(7)` for details on VCL syntax.
When neither a -f nor a -b argument are given, `varnishd` will not
start the worker process but process cli commands.
-h
Specifies the hash algorithm. See `Hash Algorithm`_ section for a list
of supported algorithms.
-i identity
Specify the identity of the Varnish server. This can be accessed
using ``server.identity`` from VCL.
-j
Specify the jailing mechanism to use. See `Jail`_ section.
-l
Specifies size of shmlog file. vsl is the space for the VSL records
[80M] and vsm is the space for stats counters [1M]. Scaling suffixes
like 'K' and 'M' can be used up to (G)igabytes.
Default is 81 Megabytes.
-M
Connect to this port and offer the command line interface. Think of
it as a reverse shell. When running with -M and there is no backend
defined the child process (the cache) will not start initially.
-n name
Specify the name for this instance. Amongst other things, this name
is used to construct the name of the directory in which `varnishd`
keeps temporary files and persistent state. If the specified name
begins with a forward slash, it is interpreted as the absolute path
to the directory which should be used for this purpose.
-P file
Write the PID of the process to the specified file.
-p
Set the parameter specified by param to the specified value, see
`List of Parameters`_ for details. This option can be used multiple
times to specify multiple parameters.
-r
Make the listed parameters read only. This gives the system
administrator a way to limit what the Varnish CLI can do. Consider
making parameters such as *cc_command*, *vcc_allow_inline_c* and
*vmod_dir* read only as these can potentially be used to escalate
privileges from the CLI.
-S secret-file
Path to a file containing a secret used for authorizing access to
the management port. If not provided a new secret will be drawn
from the system PRNG. To disable authentication use ``none``.
-s <[name=]type[,options]>
Use the specified storage backend. See `Storage Backend`_ section.
This option can be used multiple times to specify multiple storage
files. Names are referenced in logs, VCL, statistics, etc.
-T
Offer a management interface on the specified address and port. See
`Management Interface`_ for a list of management commands.
-t TTL
Specifies the default time to live (TTL) for cached objects. This is
a shortcut for specifying the *default_ttl* run-time parameter.
-V
Display the version number and exit.
-W waiter
Specifies the waiter type to use.
-x optstring
Print the optstring parameter to ``getopt(3)`` to help writing
wrapper scripts.
.. _opt_h:
Hash Algorithm
--------------
The following hash algorithms are available:
-h critbit
self-scaling tree structure. The default hash algorithm in Varnish
Cache 2.1 and onwards. In comparison to a more traditional B tree
the critbit tree is almost completely lockless. Do not change this
unless you are certain what you're doing.
-h simple_list
A simple doubly-linked list. Not recommended for production use.
-h
A standard hash table. The hash key is the CRC32 of the object's URL
modulo the size of the hash table. Each table entry points to a
list of elements which share the same hash key. The buckets
parameter specifies the number of entries in the hash table. The
default is 16383.
.. _ref-varnishd-opt_s:
Storage Backend
---------------
The following storage types are available:
-s
malloc is a memory based backend.
-s
The file backend stores data in a file on disk. The file will be
accessed using mmap.
The path is mandatory. If path points to a directory, a temporary
file will be created in that directory and immediately unlinked. If
path points to a non-existing file, the file will be created.
If size is omitted, and path points to an existing file with a size
greater than zero, the size of that file will be used. If not, an
error is reported.
Granularity sets the allocation block size. Defaults to the system
page size or the filesystem block size, whichever is larger.
-s
Persistent storage. Varnish will store objects in a file in a manner
that will secure the survival of *most* of the objects in the event
of a planned or unplanned shutdown of Varnish. The persistent
storage backend has multiple issues with it and will likely be
removed from a future version of Varnish.
.. _ref-varnishd-opt_j:
Jail
----
Varnish jails are a generalization over various platform specific
methods to reduce the privileges of varnish processes. They may have
specific options. Available jails are:
-j solaris
Reduce privileges(5) for `varnishd` and sub-process to the minimally
required set. Only available on platforms which have the setppriv(2)
call.
-j
Default on all other platforms when `varnishd` is started with an
effective uid of 0 ("as root").
With the ``unix`` jail mechanism activated, varnish will switch to
an alternative user for subprocesses and change the effective uid of
the master process whenever possible.
The optional `user` argument specifies which alternative user to
use. It defaults to ``varnish``.
The optional `ccgroup` argument specifies a group to add to varnish
subprocesses requiring access to a c-compiler. There is no default.
The optional `workuser` argument specifies an alternative user to use
for the worker process. It defaults to ``vcache``.
-j none
last resort jail choice: With jail mechanism ``none``, varnish will
run all processes with the privileges it was started with.
.. _ref-varnishd-opt_T:
Management Interface
--------------------
If the -T option was specified, `varnishd` will offer a command-line
management interface on the specified address and port. The
recommended way of connecting to the command-line management interface
is through varnishadm(1).
The commands available are documented in varnish(7).
.. _ref-varnishd-params:
RUN TIME PARAMETERS
===================
Run Time Parameter Flags
------------------------
Runtime parameters are marked with shorthand flags to avoid repeating
the same text over and over in the table below. The meaning of the
flags are:
* `experimental`
We have no solid information about good/bad/optimal values for this
parameter. Feedback with experience and observations are most
welcome.
* `delayed`
This parameter can be changed on the fly, but will not take effect
immediately.
* `restart`
The worker process must be stopped and restarted, before this
parameter takes effect.
* `reload`
The VCL programs must be reloaded for this parameter to take effect.
* `experimental`
We're not really sure about this parameter, tell us what you find.
* `wizard`
Do not touch unless you *really* know what you're doing.
* `only_root`
Only works if `varnishd` is running as root.
Default Value Exceptions on 32 bit Systems
------------------------------------------
Be aware that on 32 bit systems, certain default values are reduced
relative to the values listed below, in order to conserve VM space:
* workspace_client: 16k
* http_resp_size: 8k
* http_req_size: 12k
* gzip_stack_buffer: 4k
* thread_pool_stack: 64k
List of Parameters
------------------
This text is produced from the same text you will find in the CLI if
you use the param.show command:
.. include:: ../include/params.rst
EXIT CODES
==========
Varnish and bundled tools will, in most cases, exit with one of the
following codes
* `0` OK
* `1` Some error which could be system-dependent and/or transient
* `2` Serious configuration / parameter error - retrying with the same
configuration / parameters is most likely useless
The `varnishd` master process may also OR its exit code
* with `0x20` when the `varnishd` child process died,
* with `0x40` when the `varnishd` child process was terminated by a
signal and
* with `0x80` when a core was dumped.
SEE ALSO
========
* :ref:`varnishlog(1)`
* :ref:`varnishhist(1)`
* :ref:`varnishncsa(1)`
* :ref:`varnishstat(1)`
* :ref:`varnishtop(1)`
* :ref:`varnish-cli(7)`
* :ref:`vcl(7)`
HISTORY
=======
The `varnishd` daemon was developed by Poul-Henning Kamp in cooperation
with Verdens Gang AS and Varnish Software.
This manual page was written by Dag-Erling Smørgrav with updates by
Stig Sandbeck Mathisen , Nils Goroll and others.
COPYRIGHT
=========
This document is licensed under the same licence as Varnish
itself. See LICENCE for details.
* Copyright (c) 2007-2015 Varnish Software AS