Changes between Version 3 and Version 4 of TracFastCgi


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Timestamp:
Jan 30, 2018 2:16:51 PM (7 years ago)
Author:
trac
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  • TracFastCgi

    v3 v4  
    1 [[PageOutline]] 
    2  
    3 = Trac with FastCGI = 
    4  
    5 [http://www.fastcgi.com/ FastCGI] interface allows Trac to remain resident much like with [wiki:TracModPython mod_python] or [wiki:TracModWSGI mod_wsgi]. It is faster than external CGI interfaces which must start a new process for each request.  Additionally, it is supported by much wider variety of web servers. 
    6  
    7 Note that unlike mod_python, FastCGI supports [http://httpd.apache.org/docs/suexec.html Apache SuEXEC], i.e. run with different permissions than web server running with (`mod_wsgi` supports the `WSGIDaemonProcess` with user / group parameters to achieve the same effect). 
     1= Trac with FastCGI 
     2 
     3[[TracGuideToc]] 
     4[[PageOutline(2-5, Contents, floated)]] 
     5 
     6[http://www.fastcgi.com/ FastCGI] interface allows Trac to remain resident much like with [wiki:TracModPython mod_python] or [wiki:TracModWSGI mod_wsgi]. It is faster than external CGI interfaces which must start a new process for each request. Additionally, it is supported by a much wider variety of web servers. 
     7 
     8Note that unlike mod_python, FastCGI supports [http://httpd.apache.org/docs/suexec.html Apache SuEXEC], ie run with different permissions than the web server runs with. `mod_wsgi` supports the `WSGIDaemonProcess` with user / group parameters to achieve the same effect. 
    89 
    910'''Note for Windows:''' Trac's FastCGI does not run under Windows, as Windows does not implement `Socket.fromfd`, which is used by `_fcgi.py`. If you want to connect to IIS, you may want to try [trac:TracOnWindowsIisAjp AJP]/[trac:TracOnWindowsIisAjp ISAPI]. 
    1011 
    11 [[PageOutline(2-3,Overview,inline)]] 
    12  
    13  
    14 == Simple Apache configuration == 
    15  
    16 There are two FastCGI modules commonly available for Apache: `mod_fastcgi` and 
    17 `mod_fcgid` (preferred). The latter is more up-to-date. 
     12== Apache configuration 
     13 
     14There are two FastCGI modules commonly available for Apache: `mod_fastcgi` and `mod_fcgid` (preferred). The latter is more up-to-date. 
    1815 
    1916The following sections focus on the FCGI specific setup, see also [wiki:TracModWSGI#ConfiguringAuthentication] for configuring the authentication in Apache. 
    2017 
    21 Regardless of which cgi module is used, be sure the web server has executable permissions on the cgi-bin folder. While FastCGI will throw specific permissions errors, mod_fcgid will throw an ambiguous error if this has not been done. (Connection reset by peer: mod_fcgid: error reading data from FastCGI server)  
    22  
    23 === Set up with `mod_fastcgi` === 
     18Regardless of which cgi module is used, be sure the web server has executable permissions on the cgi-bin folder. While FastCGI will throw specific permissions errors, mod_fcgid will throw an ambiguous error if this has not been done: `Connection reset by peer: mod_fcgid: error reading data from FastCGI server`. 
     19 
     20=== Set up with `mod_fastcgi` 
     21 
    2422`mod_fastcgi` uses `FastCgiIpcDir` and `FastCgiConfig` directives that should be added to an appropriate Apache configuration file: 
    25 {{{ 
     23{{{#!apache 
    2624# Enable fastcgi for .fcgi files 
    2725# (If you're using a distro package for mod_fcgi, something like 
    … …  
    3331LoadModule fastcgi_module /usr/lib/apache2/modules/mod_fastcgi.so 
    3432}}} 
     33 
    3534Setting `FastCgiIpcDir` is optional if the default is suitable. Note that the `LoadModule` line must be after the `IfModule` group. 
    3635 
    37 Configure `ScriptAlias` or similar options as described in TracCgi, but 
    38 calling `trac.fcgi` instead of `trac.cgi`. 
     36Configure `ScriptAlias` or similar options as described in TracCgi, but calling `trac.fcgi` instead of `trac.cgi`. 
    3937 
    4038Add the following to the Apache configuration file (below the `FastCgiIpcDir` line) if you intend to set up the `TRAC_ENV` as an overall default: 
    41 {{{ 
     39{{{#!apache 
    4240FastCgiConfig -initial-env TRAC_ENV=/path/to/env/trac 
    4341}}} 
    4442 
    4543Alternatively, you can serve multiple Trac projects in a directory by adding this: 
    46 {{{ 
     44{{{#!apache 
    4745FastCgiConfig -initial-env TRAC_ENV_PARENT_DIR=/parent/dir/of/projects 
    4846}}} 
    4947 
    50 === Set up with `mod_fcgid` === 
    51 Configure `ScriptAlias` (see TracCgi for details), but call `trac.fcgi` 
    52 instead of `trac.cgi`. Note that slash at the end - it is important. 
    53 {{{ 
     48You can also specify the `PYTHON_EGG_CACHE` environment variable using a second `-initial-env` directive: 
     49{{{#!apache 
     50FastCgiConfig -initial-env TRAC_ENV=/var/lib/trac \  
     51    -initial-env PYTHON_EGG_CACHE=/var/lib/trac/plugin-cache 
     52}}} 
     53 
     54=== Set up with `mod_fcgid` 
     55 
     56Configure `ScriptAlias` (see TracCgi for details), but call `trac.fcgi` instead of `trac.cgi`: 
     57{{{#!apache 
    5458ScriptAlias /trac /path/to/www/trac/cgi-bin/trac.fcgi/ 
    5559}}} 
    5660 
    57 To set up Trac environment for `mod_fcgid` it is necessary to use 
    58 `DefaultInitEnv` directive. It cannot be used in `Directory` or 
    59 `Location` context, so if you need to support multiple projects, try 
    60 alternative environment setup below. 
    61  
    62 {{{ 
     61Note the slash at the end. 
     62 
     63To set up Trac environment for `mod_fcgid` it is necessary to use `DefaultInitEnv` directive. It cannot be used in `Directory` or `Location` context, so if you need to support multiple projects, try the alternative environment setup below: 
     64{{{#!apache 
    6365DefaultInitEnv TRAC_ENV /path/to/env/trac/ 
    6466}}} 
    6567 
    66 === alternative environment setup === 
    67 A better method to specify path to Trac environment is to embed the path 
    68 into `trac.fcgi` script itself. That doesn't require configuration of server 
    69 environment variables, works for both FastCgi modules 
    70 (and for [http://www.lighttpd.net/ lighttpd] and CGI as well): 
    71 {{{ 
     68=== Alternative environment setup 
     69 
     70A better method to specify the path to the Trac environment is to embed the path into `trac.fcgi` script itself. That doesn't require configuration of the server environment variables, works for both [trac:FastCgi] modules as well as for [http://www.lighttpd.net/ lighttpd] and CGI: 
     71{{{#!python 
    7272import os 
    7373os.environ['TRAC_ENV'] = "/path/to/projectenv" 
    7474}}} 
    75 or 
    76 {{{ 
     75 
     76or: 
     77{{{#!python 
    7778import os 
    7879os.environ['TRAC_ENV_PARENT_DIR'] = "/path/to/project/parent/dir" 
    7980}}} 
    8081 
    81 With this method different projects can be supported by using different 
    82 `.fcgi` scripts with different `ScriptAliases`. 
     82With this method different projects can be supported by using different `.fcgi` scripts with different `ScriptAliases`. 
    8383 
    8484See [https://coderanger.net/~coderanger/httpd/fcgi_example.conf this fcgid example config] which uses a !ScriptAlias directive with trac.fcgi with a trailing / like this: 
    85 {{{ 
     85{{{#!apache 
    8686ScriptAlias / /srv/tracsite/cgi-bin/trac.fcgi/ 
    8787}}} 
    8888 
    89 == Simple Cherokee Configuration == 
    90  
    91 The configuration on Cherokee's side is quite simple. You will only need to know that you can spawn Trac as an SCGI process. 
    92 You can either start it manually, or better yet, automatically by letting Cherokee spawn the server whenever it is down. 
    93 First set up an information source in cherokee-admin with a local interpreter. 
     89== Cherokee Configuration 
     90 
     91Configuring [http://cherokee-project.com/ Cherokee] with Trac is straightforward, if you spawn Trac as an SCGI process. You can either start it manually, or better yet, automatically by letting Cherokee spawn the server whenever it is down. 
     92 
     93First set up an information source in cherokee-admin with a local interpreter: 
    9494 
    9595{{{ 
    … …  
    104104 
    105105After doing this, we will just have to create a new rule managed by the SCGI handler to access Trac. It can be created in a new virtual server, trac.example.net for instance, and will only need two rules. The '''default''' one will use the SCGI handler associated to the previously created information source. 
    106 The second rule will be there to serve the few static files needed to correctly display the Trac interface. Create it as ''Directory rule'' for ''/common'' and just set it to the ''Static files'' handler and with a ''Document root'' that points to the appropriate files: ''$TRAC_LOCAL/htdocs/'' (where $TRAC_LOCAL is a directory defined by the user or the system administrator to place local trac resources). 
    107  
    108 Note:\\ 
    109 If the tracd process fails to start up, and cherokee displays a 503 error page, you might be missing the [http://trac.saddi.com/flup python-flup] package.\\ 
    110 Python-flup is a dependency which provides trac with SCGI capability. You can install it on debian based systems with: 
    111 {{{ 
     106The second rule will be there to serve the few static files needed to correctly display the Trac interface. Create it as ''Directory rule'' for ''/common'' and just set it to the ''Static files'' handler and with a ''Document root'' that points to the appropriate files: ''$TRAC_LOCAL/htdocs/'' (where $TRAC_LOCAL is a directory defined by the user or the system administrator to place local Trac resources). 
     107 
     108'''Note:''' If the tracd process fails to start up, and Cherokee displays a 503 error page, you might be missing the [http://trac.saddi.com/flup python-flup] package ([trac:#9903]). Python-flup is a dependency which provides Trac with SCGI capability. You can install it on Debian based systems with: 
     109{{{#!sh 
    112110sudo apt-get install python-flup 
    113111}}} 
    114112 
    115  
    116 == Simple Lighttpd Configuration == 
    117  
    118 The FastCGI front-end was developed primarily for use with alternative webservers, such as [http://www.lighttpd.net/ lighttpd]. 
    119  
    120 lighttpd is a secure, fast, compliant and very flexible web-server that has been optimized for high-performance 
    121 environments.  It has a very low memory footprint compared to other web servers and takes care of CPU load. 
    122  
    123 For using `trac.fcgi`(prior to 0.11) / fcgi_frontend.py (0.11) with lighttpd add the following to your lighttpd.conf: 
     113== Lighttpd Configuration 
     114 
     115The FastCGI front-end was developed primarily for use with alternative webservers, such as [http://www.lighttpd.net/ Lighttpd]. 
     116 
     117Lighttpd is a secure, fast, compliant and very flexible web-server that has been optimized for high-performance environments. It has a very low memory footprint compared to other web servers and takes care of CPU load. 
     118 
     119For using `trac.fcgi`(prior to 0.11) / fcgi_frontend.py (0.11) with Lighttpd add the following to your lighttpd.conf: 
    124120{{{ 
    125121#var.fcgi_binary="/usr/bin/python /path/to/fcgi_frontend.py" # 0.11 if installed with easy_setup, it is inside the egg directory 
    … …  
    138134}}} 
    139135 
    140 Note that you will need to add a new entry to `fastcgi.server` for each separate Trac instance that you wish to run. Alternatively, you may use the `TRAC_ENV_PARENT_DIR` variable instead of `TRAC_ENV` as described above, 
    141 and you may set one of the two in `trac.fcgi` instead of in `lighttpd.conf` 
    142 using `bin-environment` (as in the section above on Apache configuration). 
    143  
    144 Note that lighttpd has a bug related to 'SCRIPT_NAME' and 'PATH_INFO' when the uri of fastcgi.server is '/' instead of '/trac' in this example (see [trac:#2418]). This is fixed in lighttpd 1.5, and under lighttpd 1.4.23 or later the workaround is to add `"fix-root-scriptname" => "enable"` as a parameter of fastcgi.server. 
     136Note that you will need to add a new entry to `fastcgi.server` for each separate Trac instance that you wish to run. Alternatively, you may use the `TRAC_ENV_PARENT_DIR` variable instead of `TRAC_ENV` as described above, and you may set one of the two in `trac.fcgi` instead of in `lighttpd.conf` using `bin-environment`, as in the section above on Apache configuration. 
     137 
     138Note that Lighttpd has a bug related to 'SCRIPT_NAME' and 'PATH_INFO' when the uri of fastcgi.server is '/' instead of '/trac' in this example (see [trac:#2418]). This is fixed in Lighttpd 1.5, and under Lighttpd 1.4.23 or later the workaround is to add `"fix-root-scriptname" => "enable"` as a parameter of fastcgi.server. 
    145139 
    146140For using two projects with lighttpd add the following to your `lighttpd.conf`: 
    … …  
    166160                ) 
    167161}}} 
    168 Note that field values are different.  If you prefer setting the environment 
    169 variables in the `.fcgi` scripts, then copy/rename `trac.fcgi`, e.g., to 
    170 `first.fcgi` and `second.fcgi`, and reference them in the above settings. 
    171 Note that the above will result in different processes in any event, even 
    172 if both are running from the same `trac.fcgi` script. 
    173  
    174 {{{ 
    175 #!div class=important 
    176 '''Note''' It's very important the order on which server.modules are loaded, if mod_auth is not loaded '''BEFORE''' mod_fastcgi, then the server will fail to authenticate the user. 
     162 
     163Note that the field values are different. If you prefer setting the environment variables in the `.fcgi` scripts, then copy/rename `trac.fcgi`, eg to `first.fcgi` and `second.fcgi`, and reference them in the above settings. 
     164Note that the above will result in different processes in any event, even if both are running from the same `trac.fcgi` script. 
     165 
     166{{{#!div class=important 
     167'''Note:''' The order in which the server.modules are loaded is very important: if mod_auth is not loaded '''before''' mod_fastcgi, then the server will fail to authenticate the user. 
    177168}}} 
    178169 
    … …  
    213204               ) 
    214205 
    215  
    216 }}} 
    217 Note that lighttpd (I use version 1.4.3) stopped if password file doesn't exist. 
    218  
    219 Note that lighttpd doesn't support 'valid-user' in versions prior to 1.3.16. 
    220  
    221 Conditional configuration is also useful for mapping static resources, i.e. serving out images and CSS directly instead of through FastCGI: 
     206}}} 
     207 
     208Note that Lighttpd (v1.4.3) stops if the password file doesn't exist. 
     209 
     210Note that Lighttpd doesn't support 'valid-user' in versions prior to 1.3.16. 
     211 
     212Conditional configuration is also useful for mapping static resources, ie serving out images and CSS directly instead of through FastCGI: 
    222213{{{ 
    223214# Aliasing functionality is needed 
    … …  
    243234} 
    244235}}} 
     236 
    245237The technique can be easily adapted for use with multiple projects by creating aliases for each of them, and wrapping the fastcgi.server declarations inside conditional configuration blocks. 
    246 Also there is another way to handle multiple projects and it's to use TRAC_ENV_PARENT_DIR instead of TRAC_ENV and use global auth, let's see an example: 
     238 
     239Also there is another way to handle multiple projects and it uses `TRAC_ENV_PARENT_DIR` instead of `TRAC_ENV` as well as global authentication: 
    247240{{{ 
    248241#  This is for handling multiple projects 
    … …  
    274267}}} 
    275268 
    276 Changing date/time format also supported by lighttpd over environment variable LC_TIME 
     269Changing date/time format also supported by lighttpd over environment variable LC_TIME: 
    277270{{{ 
    278271fastcgi.server = ("/trac" => 
    … …  
    288281                 ) 
    289282}}} 
     283 
    290284For details about languages specification see [trac:TracFaq TracFaq] question 2.13. 
    291285 
    292286Other important information like the [wiki:TracInstall#MappingStaticResources mapping static resources advices] are useful for non-fastcgi specific installation aspects. 
    293 ] 
    294  
    295 Relaunch lighttpd, and browse to `http://yourhost.example.org/trac` to access Trac. 
    296  
    297 Note about running lighttpd with reduced permissions: 
    298  
    299 If nothing else helps and trac.fcgi doesn't start with lighttpd settings `server.username = "www-data"`, `server.groupname = "www-data"`, then in the `bin-environment` section set `PYTHON_EGG_CACHE` to the home directory of `www-data` or some other directory accessible to this account for writing. 
    300  
    301  
    302 == Simple !LiteSpeed Configuration == 
     287 
     288Relaunch Lighttpd and browse to `http://yourhost.example.org/trac` to access Trac. 
     289 
     290Note about running Lighttpd with reduced permissions: If nothing else helps and trac.fcgi doesn't start with Lighttpd settings `server.username = "www-data"`, `server.groupname = "www-data"`, then in the `bin-environment` section set `PYTHON_EGG_CACHE` to the home directory of `www-data` or some other directory accessible to this account for writing. 
     291 
     292== !LiteSpeed Configuration 
    303293 
    304294The FastCGI front-end was developed primarily for use with alternative webservers, such as [http://www.litespeedtech.com/ LiteSpeed]. 
    … …  
    306296!LiteSpeed web server is an event-driven asynchronous Apache replacement designed from the ground-up to be secure, scalable, and operate with minimal resources. !LiteSpeed can operate directly from an Apache config file and is targeted for business-critical environments. 
    307297 
    308  1. Please make sure you have first have a working install of a Trac project. Test install with “tracd” first. 
    309  
    310  2. Create a Virtual Host for this setup. From now on we will refer to this vhost as !TracVhost. For this tutorial we will be assuming that your trac project will be accessible via: 
    311  
     298 1. Please make sure you have a working install of a Trac project. Test install with "tracd" first. 
     299 1. Create a Virtual Host for this setup. From now on we will refer to this vhost as !TracVhost. For this tutorial we will be assuming that your Trac project will be accessible via: 
    312300{{{ 
    313301http://yourdomain.com/trac/ 
    314302}}} 
    315  
    316  3. Go “!TracVhost → External Apps” tab and create a new “External Application”. 
    317  
     303 1. Go "!TracVhost → External Apps" tab and create a new "External Application": 
    318304{{{ 
    319305Name: MyTracFCGI         
    … …  
    331317Instances: 10 
    332318}}} 
    333  
    334  4. Optional. If you need to use htpasswd based authentication. Go to “!TracVhost → Security” tab and create a new security “Realm”. 
    335  
    336 {{{ 
     319 1. Optional: If you need to use htpasswd based authentication. Go to "!TracVhost → Security" tab and create a new security Realm: 
     320 {{{ 
    337321DB Type: Password File 
    338322Realm Name: MyTracUserDB               <--- any name you wish and referenced later 
    339323User DB Location: /fullpathto/htpasswd <--- path to your htpasswd file 
    340324}}} 
    341  
    342 If you don’t have a htpasswd file or don’t know how to create the entries within one, go to http://sherylcanter.com/encrypt.php, to generate the user:password combos. 
    343  
    344  5. Go to “!PythonVhost → Contexts” and create a new “FCGI Context”. 
    345  
    346 {{{ 
     325 If you don’t have a htpasswd file or don’t know how to create the entries within one, go to http://sherylcanter.com/encrypt.php, to generate the user:password combos. 
     326 1. Go to "!PythonVhost → Contexts" and create a new FCGI Context: 
     327 {{{ 
    347328URI: /trac/                              <--- URI path to bind to python fcgi app we created     
    348 Fast CGI App: [VHost Level] MyTractFCGI  <--- select the trac fcgi extapp we just created 
     329Fast CGI App: [VHost Level] MyTractFCGI  <--- select the Trac fcgi extapp we just created 
    349330Realm: TracUserDB                        <--- only if (4) is set. select realm created in (4) 
    350331}}} 
    351  
    352  6. Modify `/fullpathto/mytracproject/conf/trac.ini` 
    353  
    354 {{{ 
     332 1. Modify `/fullpathto/mytracproject/conf/trac.ini`: 
     333 {{{ 
    355334#find/set base_rul, url, and link variables 
    356335base_url = http://yourdomain.com/trac/ <--- base url to generate correct links to 
    … …  
    358337link = http://yourdomain.com/trac/     <--- link of graphic logo 
    359338}}} 
    360  
    361  7. Restart !LiteSpeed, “lswsctrl restart”, and access your new Trac project at:  
    362  
    363 {{{ 
    364 http://yourdomain.com/trac/ 
    365 }}} 
    366  
    367  
    368 == Simple Nginx Configuration == 
    369  
    370 Nginx is able to communicate with FastCGI processes, but can not spawn them. So you need to start FastCGI server for Trac separately. 
     339 1. Restart !LiteSpeed: `lswsctrl restart`, and access your new Trac project at {{{http://yourdomain.com/trac/}}}. 
     340 
     341== Nginx Configuration 
     342 
     343[http://nginx.org/en/ Nginx] is able to communicate with FastCGI processes, but can not spawn them. So you need to start FastCGI server for Trac separately. 
    371344 
    372345 1. Nginx configuration with basic authentication handled by Nginx - confirmed to work on 0.6.32 
    373 {{{ 
     346 {{{#!nginx 
    374347    server { 
    375348        listen       10.9.8.7:443; 
    … …  
    386359        ssl_prefer_server_ciphers   on; 
    387360 
    388         # (Or ``^/some/prefix/(.*)``. 
    389         if ($uri ~ ^/(.*)) { 
    390              set $path_info /$1; 
     361        # it makes sense to serve static resources through Nginx (or ``~ [/some/prefix]/chrome/(.*)``) 
     362        location ~ /chrome/(.*) { 
     363             alias /home/trac/instance/static/htdocs/$1; 
    391364        } 
    392365 
    393         # it makes sense to serve static resources through Nginx 
    394         location /chrome/ { 
    395              alias /home/trac/instance/static/htdocs/; 
    396         } 
    397  
    398         # You can copy this whole location to ``location [/some/prefix]/login`` 
     366        # You can copy this whole location to ``location [/some/prefix](/login)`` 
    399367        # and remove the auth entries below if you want Trac to enforce 
    400368        # authorization where appropriate instead of needing to authenticate 
    401369        # for accessing the whole site. 
    402         # (Or ``location /some/prefix``.) 
    403         location / { 
     370        # (Or ``~ location /some/prefix(/.*)``.) 
     371        location ~ (/.*) { 
    404372            auth_basic            "trac realm"; 
    405373            auth_basic_user_file /home/trac/htpasswd; 
    … …  
    415383            # (Or ``fastcgi_param  SCRIPT_NAME  /some/prefix``.) 
    416384            fastcgi_param  SCRIPT_NAME        ""; 
    417             fastcgi_param  PATH_INFO          $path_info; 
     385            fastcgi_param  PATH_INFO          $1; 
    418386 
    419387            ## WSGI NEEDED VARIABLES - trac warns about them 
    … …  
    438406    } 
    439407}}} 
    440  
    441  2. Modified trac.fcgi: 
    442  
    443 {{{ 
     408 1. Modified trac.fcgi: 
     409 {{{#!python 
    444410#!/usr/bin/env python 
    445411import os 
    … …  
    472438 
    473439}}} 
    474  
    475  3. reload nginx and launch trac.fcgi like that: 
    476  
    477 {{{ 
     440 1. Reload nginx and launch trac.fcgi:  
     441 {{{#!sh 
    478442trac@trac.example ~ $ ./trac-standalone-fcgi.py  
    479443}}} 
    480444 
    481445The above assumes that: 
    482  * There is a user named 'trac' for running trac instances and keeping trac environments in its home directory. 
    483  * `/home/trac/instance` contains a trac environment 
     446 * There is a user named 'trac' for running Trac instances and keeping Trac environments in its home directory 
     447 * `/home/trac/instance` contains a Trac environment 
    484448 * `/home/trac/htpasswd` contains authentication information 
    485  * `/home/trac/run` is owned by the same group the nginx runs under 
     449 * `/home/trac/run` is owned by the same group the Nginx runs under 
    486450  * and if your system is Linux the `/home/trac/run` has setgid bit set (`chmod g+s run`) 
    487   * and patch from ticket #T7239 is applied, or you'll have to fix the socket file permissions every time 
    488  
    489 Unfortunately nginx does not support variable expansion in fastcgi_pass directive.  
    490 Thus it is not possible to serve multiple trac instances from one server block.  
    491  
    492 If you worry enough about security, run trac instances under separate users.  
    493  
    494 Another way to run trac as a FCGI external application is offered in ticket #T6224 
     451  * and patch from [trac:#7239] is applied, or you'll have to fix the socket file permissions every time 
     452 
     453Unfortunately Nginx does not support variable expansion in fastcgi_pass directive.  
     454Thus it is not possible to serve multiple Trac instances from one server block.  
     455 
     456If you worry enough about security, run Trac instances under separate users.  
     457 
     458Another way to run Trac as a FCGI external application is offered in [trac:#6224]. 
    495459 
    496460---- 
    497 See also:  TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracCgi CGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe] 
     461See also: TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracCgi CGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe]