Пункт 1. Upgrading to 2.4 from 2.2
In order to assist folks upgrading, we maintain a document
describing information critical to existing Apache HTTP Server users. These
are intended to be brief notes, and you should be able to find
more information in either the New Features document, or in
the src/CHANGES file. Application and module developers
can find a summary of API changes in the API updates overview.
This document describes changes in server behavior that might
require you to change your configuration or how you use the server
in order to continue using 2.4 as you are currently using 2.2.
To take advantage of new features in 2.4, see the New Features
document.
This document describes only the changes from 2.2 to 2.4. If you
are upgrading from version 2.0, you should also consult the 2.0 to 2.2
upgrading document.
Compile-Time Configuration Changes
The compilation process is very similar to the one used in
version 2.2. Your old configure command line (as
found in build/config.nice in the installed server
directory) can be used in most cases. There are some changes in
the default settings. Some details of changes:
- These modules have been removed: mod_authn_default,
mod_authz_default, mod_mem_cache. If you were using
mod_mem_cache in 2.2, look at
mod_cache_disk in
2.4.
- All load balancing implementations have been moved to
individual, self-contained mod_proxy submodules, e.g.
mod_lbmethod_bybusyness . You might need
to build and load any of these that your configuration
uses.
- Platform support has been removed for BeOS, TPF, and
even older platforms such as A/UX, Next, and Tandem. These were
believed to be broken anyway.
- configure: dynamic modules (DSO) are built by default
- configure: By default, only a basic set of modules is loaded. The
other
LoadModule directives are commented
out in the configuration file.
- configure: the "most" module set gets built by default
- configure: the "reallyall" module set adds developer modules
to the "all" set
Run-Time Configuration Changes
There have been significant changes in authorization configuration,
and other minor configuration changes, that could require changes to your 2.2
configuration files before using them for 2.4.
Authorization
Any configuration file that uses authorization will likely
need changes.
You should review the Authentication,
Authorization and Access Control Howto, especially the section
Beyond just authorization
which explains the new mechanisms for controlling the order in
which the authorization directives are applied.
Directives that control how authorization modules respond when they don't match
the authenticated user have been removed: This includes
AuthzLDAPAuthoritative, AuthzDBDAuthoritative, AuthzDBMAuthoritative,
AuthzGroupFileAuthoritative, AuthzUserAuthoritative,
and AuthzOwnerAuthoritative. These directives have been replaced by the
more expressive RequireAny ,
RequireNone , and
RequireAll .
If you use mod_authz_dbm , you must port your
configuration to use Require dbm-group ... in place
of Require group ... .
Access control
In 2.2, access control based on client hostname, IP address,
and other characteristics of client requests was done using the
directives Order , Allow , Deny , and Satisfy .
In 2.4, such access control is done in the same way as other
authorization checks, using the new module
mod_authz_host . The old access control idioms
should be replaced by the new authentication mechanisms,
although for compatibility with old configurations, the new
module mod_access_compat is provided.
Mixing old and new directives
Mixing old directives like Order , Allow or Deny with new ones like
Require is technically possible
but discouraged. mod_access_compat was created to support
configurations containing only old directives to facilitate the 2.4 upgrade.
Please check the examples below to get a better idea about issues that might arise.
Here are some examples of old and new ways to do the same
access control.
In this example, there is no authentication and all requests are denied.
2.2 configuration:
Order deny,allow
Deny from all
2.4 configuration:
Require all denied
In this example, there is no authentication and all requests are allowed.
2.2 configuration:
Order allow,deny
Allow from all
2.4 configuration:
Require all granted
In the following example, there is no authentication and all hosts in the example.org domain
are allowed access; all other hosts are denied access.
2.2 configuration:
Order Deny,Allow
Deny from all
Allow from example.org
2.4 configuration:
Require host example.org
In the following example, mixing old and new directives leads to
unexpected results.
Mixing old and new directives: NOT WORKING AS EXPECTED
DocumentRoot "/var/www/html"
<Directory "/">
AllowOverride None
Order deny,allow
Deny from all
</Directory>
<Location "/server-status">
SetHandler server-status
Require local
</Location>
access.log - GET /server-status 403 127.0.0.1
error.log - AH01797: client denied by server configuration: /var/www/html/server-status
Why httpd denies access to servers-status even if the configuration seems to allow it?
Because mod_access_compat directives take precedence
over the mod_authz_host one in this configuration
merge scenario.
This example conversely works as expected:
Mixing old and new directives: WORKING AS EXPECTED
DocumentRoot "/var/www/html"
<Directory "/">
AllowOverride None
Require all denied
</Directory>
<Location "/server-status">
SetHandler server-status
Order deny,allow
Deny from all
Allow From 127.0.0.1
</Location>
access.log - GET /server-status 200 127.0.0.1
So even if mixing configuration is still
possible, please try to avoid it when upgrading: either keep old directives and then migrate
to the new ones on a later stage or just migrate everything in bulk.
In many configurations with authentication, where the value of the
Satisfy was the default of ALL, snippets
that simply disabled host-based access control are omitted:
2.2 configuration:
Order Deny,Allow
Deny from all
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
Require valid-user
2.4 configuration:
# No replacement needed
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
Require valid-user
In configurations where both authentication and access control were meaningfully combined, the
access control directives should be migrated. This example allows requests meeting both criteria:
2.2 configuration:
Order allow,deny
Deny from all
# Satisfy ALL is the default
Satisfy ALL
Allow from 127.0.0.1
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
Require valid-user
2.4 configuration:
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
<RequireAll>
Require valid-user
Require ip 127.0.0.1
</RequireAll>
In configurations where both authentication and access control were meaningfully combined, the
access control directives should be migrated. This example allows requests meeting either criteria:
2.2 configuration:
Order allow,deny
Deny from all
Satisfy any
Allow from 127.0.0.1
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
Require valid-user
2.4 configuration:
AuthBasicProvider File
AuthUserFile /example.com/conf/users.passwd
AuthName secure
# Implicitly <RequireAny>
Require valid-user
Require ip 127.0.0.1
Other configuration changes
Some other small adjustments may be necessary for particular
configurations as discussed below.
-
MaxRequestsPerChild has been renamed to
MaxConnectionsPerChild ,
describes more accurately what it does. The old name is still
supported.
-
MaxClients has been renamed to
MaxRequestWorkers ,
which describes more accurately what it does. For async MPMs, like
event , the maximum number of clients is not
equivalent than the number of worker threads. The old name is still
supported.
- The
DefaultType
directive no longer has any effect, other than to emit a
warning if it's used with any value other than
none . You need to use other configuration
settings to replace it in 2.4.
-
AllowOverride now
defaults to None .
-
EnableSendfile now
defaults to Off.
-
FileETag now
defaults to "MTime Size" (without INode).
-
mod_dav_fs : The format of the DavLockDB file has changed for
systems with inodes. The old DavLockDB file must be deleted on
upgrade.
-
KeepAlive only
accepts values of On or Off .
Previously, any value other than "Off" or "0" was treated as
"On".
- Directives AcceptMutex, LockFile, RewriteLock, SSLMutex,
SSLStaplingMutex, and WatchdogMutexPath have been replaced
with a single
Mutex
directive. You will need to evaluate any use of these removed
directives in your 2.2 configuration to determine if they can
just be deleted or will need to be replaced using Mutex .
-
mod_cache : CacheIgnoreURLSessionIdentifiers
now does an exact match against the query string instead of a
partial match. If your configuration was using partial
strings, e.g. using sessionid to match
/someapplication/image.gif;jsessionid=123456789 ,
then you will need to change to the full string
jsessionid .
-
mod_cache : The second parameter to
CacheEnable only
matches forward proxy content if it begins with the correct
protocol. In 2.2 and earlier, a parameter of '/' matched all
content.
-
mod_ldap : LDAPTrustedClientCert is now
consistently a per-directory setting only. If you use this
directive, review your configuration to make sure it is
present in all the necessary directory contexts.
-
mod_filter : FilterProvider syntax has changed and
now uses a boolean expression to determine if a filter is applied.
-
mod_include :
- The
#if expr element now uses the new expression parser. The old syntax can be
restored with the new directive SSILegacyExprParser .
- An SSI* config directive in directory scope no longer causes
all other per-directory SSI* directives to be reset to their
default values.
-
mod_charset_lite : The DebugLevel
option has been removed in favour of per-module LogLevel configuration.
-
mod_ext_filter : The DebugLevel
option has been removed in favour of per-module LogLevel configuration.
-
mod_proxy_scgi : The default setting for
PATH_INFO has changed from httpd 2.2, and
some web applications will no longer operate properly with
the new PATH_INFO setting. The previous setting
can be restored by configuring the proxy-scgi-pathinfo
variable.
-
mod_ssl : CRL based revocation checking
now needs to be explicitly configured through SSLCARevocationCheck .
-
mod_substitute : The maximum line length is now
limited to 1MB.
-
mod_reqtimeout : If the module is loaded, it
will now set some default timeouts.
-
mod_dumpio : DumpIOLogLevel
is no longer supported. Data is always logged at LogLevel trace7 .
- On Unix platforms, piped logging commands configured using
either
ErrorLog or
CustomLog were invoked using
/bin/sh -c in 2.2 and earlier. In 2.4 and later,
piped logging commands are executed directly. To restore the
old behaviour, see the piped logging
documentation.
Misc Changes
-
mod_autoindex : will now extract titles and
display descriptions for .xhtml files, which were previously
ignored.
-
mod_ssl : The default format of the *_DN
variables has changed. The old format can still be used with the new
LegacyDNStringFormat argument to SSLOptions . The SSLv2 protocol is
no longer supported. SSLProxyCheckPeerCN
and SSLProxyCheckPeerExpire
now default to On, causing proxy requests to HTTPS hosts
with bad or outdated certificates to fail with a 502 status code (Bad
gateway)
-
htpasswd now uses MD5 hash by default on
all platforms.
- The
NameVirtualHost
directive no longer has any effect, other than to emit a
warning. Any address/port combination appearing in multiple
virtual hosts is implicitly treated as a name-based virtual host.
-
mod_deflate will now skip compression if it knows
that the size overhead added by the compression is larger than the data
to be compressed.
- Multi-language error documents from 2.2.x may not work unless
they are adjusted to the new syntax of
mod_include 's
#if expr= element or the directive
SSILegacyExprParser is
enabled for the directory containing the error documents.
- The functionality provided by
mod_authn_alias
in previous versions (i.e., the AuthnProviderAlias directive)
has been moved into mod_authn_core .
- The RewriteLog and RewriteLogLevel directives have been removed.
This functionality is now provided by configuring the appropriate
level of logging for the
mod_rewrite module using
the LogLevel directive.
See also the mod_rewrite logging
section.
Third Party Modules
All modules must be recompiled for 2.4 before being loaded.
Many third-party modules designed for version 2.2 will
otherwise work unchanged with the Apache HTTP Server version 2.4.
Some will require changes; see the API
update overview.
Common problems when upgrading
- Startup errors:
-
Invalid command 'User', perhaps misspelled or defined by a module not included in the server configuration - load module mod_unixd
-
Invalid command 'Require', perhaps misspelled or defined by a module not included in the server configuration , or
Invalid command 'Order', perhaps misspelled or defined by a module not included in the server configuration
- load module mod_access_compat , or update configuration to 2.4 authorization directives.
-
Ignoring deprecated use of DefaultType in line NN of /path/to/apache2.conf - remove DefaultType
and replace with other configuration settings.
-
Invalid command 'AddOutputFilterByType', perhaps misspelled
or defined by a module not included in the server configuration
- AddOutputFilterByType
has moved from the core to mod_filter, which must be loaded.
- Errors serving requests:
-
configuration error: couldn't check user: /path -
load module mod_authn_core .
-
.htaccess files aren't being processed - Check for an
appropriate AllowOverride directive;
the default changed to None in 2.4.
