Varnish CentOS - 错误 503 后端获取失败

Posted 2023-03-10

【中文标题】Varnish CentOS - 错误 503 后端获取失败

【英文标题】：Varnish CentOS - Error 503 Backend fetch failed

【发布时间】：2016-01-17 13:35:08

【问题描述】：

我们安装了 Varnish，但效果并不理想。

我设置 Varnish 监听 80 端口，Apache 监听 8080。 当我重新启动清漆和 apache 页面继续加载和加载.. 我还尝试禁用 CSF..

之后显示： 错误 503 后端提取失败 上师冥想： 西ID：2818051

有人知道如何解决这个问题吗？

规格：2.6.32-604.30.3.lve1.3.63.el6.x86_64 #1 SMP Sun Sep 27 06:34:10 EDT 2015 x86_64 x86_64 x86_64 GNU/Linux CentOS - Cloudlinux 6.7

配置文件下方：

httpd.conf

#
# This is the main Apache HTTP server configuration file.  It contains the
# configuration directives that give the server its instructions.
# See <URL:http://httpd.apache.org/docs/2.4> for detailed information.
# In particular, see
# <URL:http://httpd.apache.org/docs/2.4/mod/directives.html>
# for a discussion of each configuration directive.
#
# Do NOT simply read the instructions in here without understanding
# what they do.  They're here only as hints or reminders.  If you are unsure
# consult the online docs. You have been warned.

#
# ServerRoot: The top of the directory tree under which the server's
# configuration, error, and log files are kept.
#
# Do not add a slash at the end of the directory path.  If you point
# ServerRoot at a non-local disk, be sure to specify a local disk on the
# Mutex directive, if file-based mutexes are used.  If you wish to share the
# same ServerRoot for multiple httpd daemons, you will need to change at
# least PidFile.
#
ServerRoot "/etc/httpd"
HostnameLookups Off
#
# Listen: Allows you to bind Apache to specific IP addresses and/or
# ports, instead of the default. See also the <VirtualHost>
# directive.
#
# Change this to Listen on specific IP addresses as shown below to
# prevent Apache from glomming onto all bound IP addresses.
#
#Listen 12.34.56.78:80
Listen 80

<IfModule unixd_module>
#
# If you wish httpd to run as a different user or group, you must run
# httpd as root initially and it will switch.
#
# User/Group: The name (or #number) of the user/group to run httpd as.
# It is usually good practice to create a dedicated user and group for
# running httpd, as with most system services.
#
User apache
Group apache
</IfModule>

#LoadModule dummy_module /usr/lib/apache/mod_dummy.so
Include /etc/httpd/conf/extra/httpd-phpmodules.conf

#
# ServerAdmin: Your address, where problems with the server should be
# e-mailed.  This address appears on some server-generated pages, such
# as error documents.  e.g. [e-mail]
#
ServerAdmin admin@localhost
DocumentRoot "/var/www/html"

<IfModule dir_module>

<IfModule dir_module>
    DirectoryIndex index.html index.htm index.shtml index.php index.php5 index.php4 index.php3 index.phtml index.cgi
</IfModule>

#
# The following lines prevent .htaccess and .htpasswd files from being
# viewed by Web clients.
#
<Files ".ht*">
    Require all denied
</Files>

#
# The following lines prevent .user.ini files from being viewed by Web clients.
#
<Files ".user.ini">
    Require all denied
</Files>

#
# ErrorLog: The location of the error log file.
# If you do not specify an ErrorLog directive within a <VirtualHost>
# container, error messages relating to that virtual host will be
# logged here.  If you *do* define an error logfile for a <VirtualHost>
# container, that host's errors will be logged there and not here.
#
ErrorLog /var/log/httpd/error_log

#
# LogLevel: Control the number of messages logged to the error_log.
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
#
LogLevel warn

<IfModule log_config_module>
    #replace %b with %O for more accurate logging
    <IfModule mod_logio.c>
      LogFormat "%a %l %u %t \"%r\" %>s %O \"%Refereri\" \"%User-Agenti\"" combined
      LogFormat "%a %l %u %t \"%r\" %>s %O" common
      LogFormat "%O %I" bytes

      LogFormat "%a %l %u %t \"%r\" %>s %b \"%Refereri\" \"%User-Agenti\" %I %O" combinedio
    </IfModule>

    CustomLog /var/log/httpd/access_log common
</IfModule>

<IfModule alias_module>
    # Include some DirectAdmin alias
    Include conf/extra/httpd-alias.conf
</IfModule>

#DefaultType text/plain

<IfModule mime_module>
    TypesConfig conf/mime.types
    AddType application/x-gzip .tgz
    AddEncoding x-compress .Z
    AddEncoding x-gzip .gz .tgz
    AddType application/x-compress .Z
    AddType application/x-gzip .gz .tgz
    AddHandler cgi-script .cgi
    AddHandler type-map var
    AddType text/html .shtml
    AddOutputFilter INCLUDES .shtml
        AddType video/x-ms-asf .avi
        AddType video/mpeg .mpg
        AddType video/mpeg .mpeg
        AddType video/quicktime .mov
        AddType video/x-ms-wmv .wmv
</IfModule>

#
# MaxRanges: Maximum number of Ranges in a request before
# returning the entire resource, or one of the special
# values 'default', 'none' or 'unlimited'.
# Default setting is to accept 200 Ranges.
#MaxRanges unlimited

#
# EnableMMAP and EnableSendfile: On systems that support it,
# memory-mapping or the sendfile syscall may be used to deliver
# files.  This usually improves server performance, but must
# be turned off when serving from networked-mounted
# filesystems or if support for these functions is otherwise
# broken on your system.
# Defaults: EnableMMAP On, EnableSendfile Off
#
#EnableMMAP off
#EnableSendfile off

#######################################################################################
# For user configurations not maintained by DirectAdmin. Empty by default.
#######################################################################################

Include conf/extra/httpd-includes.conf

#######################################################################################
# Supplemental configuration
#######################################################################################

# Options and AllowOverrides
Include conf/extra/httpd-directories.conf

# nginx reverse proxy configuration
Include conf/extra/httpd-nginx.conf

# Server-pool management (MPM specific)
Include conf/extra/httpd-mpm.conf

# Multi-language error messages
Include conf/extra/httpd-multilang-errordoc.conf

# Fancy directory listings
Include conf/extra/httpd-autoindex.conf

# Language settings
Include conf/extra/httpd-languages.conf

# User home directories
#Include conf/extra/httpd-userdir.conf

# Real-time info on requests and configuration
Include conf/extra/httpd-info.conf

# Suphp
Include conf/extra/httpd-suphp.conf

# Local access to the Apache HTTP Server Manual
#Include conf/extra/httpd-manual.conf

# Distributed authoring and versioning (WebDAV)
Include conf/extra/httpd-dav.conf

# Various default settings
Include conf/extra/httpd-default.conf

# Secure (SSL/TLS) connections
Include conf/extra/httpd-ssl.conf

# Deflate module settings
Include conf/extra/httpd-deflate.conf

#######################################################################################
# Do not change anything in files below, because they are rewritten by DirectAdmin    #
#######################################################################################

# This is needed for PHP
Include conf/extra/httpd-php-handlers.conf

# Virtual hosts
Include conf/extra/httpd-vhosts.conf

# All the DirectAdmin vhosts
Include conf/extra/directadmin-vhosts.conf

#######################################################################################
# End of included files that are rewritten by DirectAdmin                             #
#######################################################################################

<IfModule ssl_module>
SSLRandomSeed startup builtin
SSLRandomSeed connect builtin
</IfModule>

# Alias for RoundCube webmail
# Alias /roundcube /var/www/html/roundcube/

default.vcl

#
# This is an example VCL file for Varnish.
#
# It does not do anything by default, delegating control to the
# builtin VCL. The builtin VCL is called when there is no explicit
# return statement.
#
# See the VCL chapters in the Users Guide at https://www.varnish-cache.org/docs/
# and http://varnish-cache.org/trac/wiki/VCLExamples for more examples.

# Marker to tell the VCL compiler that this VCL has been adapted to the
# new 4.0 format.
vcl 4.0;

# Default backend definition. Set this to point to your content server.
backend default 
    .host = "149.210.175.70";
    .port = "80";


sub vcl_recv 
    # Happens before we check if we have this in cache already.
    #
    # Typically you clean up the request here, removing cookies you don't need,
    # rewriting the request, etc.


sub vcl_backend_response 
    # Happens after we have read the response headers from the backend.
    #
    # Here you clean the response headers, removing silly Set-Cookie headers
    # and other mistakes your backend does.


sub vcl_deliver 
    # Happens when we have all the pieces we need, and are about to send the
    # response to the client.
    #
    # You can do accounting or modifying the final object here.

系统配置/清漆

# Configuration file for varnish
#
# /etc/init.d/varnish expects the variable $DAEMON_OPTS to be set from this
# shell script fragment.
#

# Maximum number of open files (for ulimit -n)
NFILES=131072

# Locked shared memory (for ulimit -l)
# Default log size is 82MB + header
MEMLOCK=82000

# Maximum number of threads (for ulimit -u)
NPROCS="unlimited"

# Maximum size of corefile (for ulimit -c). Default in Fedora is 0
# DAEMON_COREFILE_LIMIT="unlimited"

# Set this to 1 to make init script reload try to switch vcl without restart.
# To make this work, you need to set the following variables
# explicit: VARNISH_VCL_CONF, VARNISH_ADMIN_LISTEN_ADDRESS,
# VARNISH_ADMIN_LISTEN_PORT, VARNISH_SECRET_FILE, or in short,
# use Alternative 3, Advanced configuration, below
RELOAD_VCL=1

# This file contains 4 alternatives, please use only one.

## Alternative 1, Minimal configuration, no VCL
#
# Listen on port 6081, administration on localhost:6082, and forward to
# content server on localhost:8080.  Use a fixed-size cache file.
#
DAEMON_OPTS="-a :80 \
             -T localhost:6082 \
             -b localhost:8080 \
             -u varnish -g varnish \
             -s file,/var/lib/varnish/varnish_storage.bin,1G"


## Alternative 2, Configuration with VCL
#
# Listen on port 6081, administration on localhost:6082, and forward to
# one content server selected by the vcl file, based on the request.  Use a
# fixed-size cache file.
#
#DAEMON_OPTS="-a :6081 \
#             -T localhost:6082 \
#             -f /etc/varnish/default.vcl \
#             -u varnish -g varnish \
#             -S /etc/varnish/secret \
#             -s file,/var/lib/varnish/varnish_storage.bin,1G"


## Alternative 3, Advanced configuration
#
# See varnishd(1) for more information.
#
# # Main configuration file. You probably want to change it :)
VARNISH_VCL_CONF=/etc/varnish/default.vcl
#
# # Default address and port to bind to
# # Blank address means all IPv4 and IPv6 interfaces, otherwise specify
# # a host name, an IPv4 dotted quad, or an IPv6 address in brackets.
# VARNISH_LISTEN_ADDRESS=
VARNISH_LISTEN_PORT=80
#
# # Telnet admin interface listen address and port
VARNISH_ADMIN_LISTEN_ADDRESS=127.0.0.1
VARNISH_ADMIN_LISTEN_PORT=6082
#
# # Shared secret file for admin interface
VARNISH_SECRET_FILE=/etc/varnish/secret
#
# # The minimum number of worker threads to start
VARNISH_MIN_THREADS=50
#
# # The Maximum number of worker threads to start
VARNISH_MAX_THREADS=1000
#
# # Idle timeout for worker threads
VARNISH_THREAD_TIMEOUT=120
#
# # Cache file size: in bytes, optionally using k / M / G / T suffix,
# # or in percentage of available disk space using the % suffix.
VARNISH_STORAGE_SIZE=256M
#
# # Backend storage specification
VARNISH_STORAGE="malloc,$VARNISH_STORAGE_SIZE"
#
# # Default TTL used when the backend does not specify one
VARNISH_TTL=120
#
# # DAEMON_OPTS is used by the init script.  If you add or remove options, make
# # sure you update this section, too.
DAEMON_OPTS="-a $VARNISH_LISTEN_ADDRESS:$VARNISH_LISTEN_PORT \
             -f $VARNISH_VCL_CONF \
             -T $VARNISH_ADMIN_LISTEN_ADDRESS:$VARNISH_ADMIN_LISTEN_PORT \
             -t $VARNISH_TTL \
             -p thread_pool_min=$VARNISH_MIN_THREADS \
             -p thread_pool_max=$VARNISH_MAX_THREADS \
             -p thread_pool_timeout=$VARNISH_THREAD_TIMEOUT \
             -u varnish -g varnish \
             -S $VARNISH_SECRET_FILE \
             -s $VARNISH_STORAGE"
#


## Alternative 4, Do It Yourself. See varnishd(1) for more information.
#
# DAEMON_OPTS=""

【参考方案1】：

您的 httpd.conf 告诉 Apache 也侦听端口 80。 Apache 或 Varnish 都无法启动。

【参考方案2】：

Varnish 在您的公共服务器上侦听端口 80。 Apache 可以在端口 80 上运行 - 但在单独的服务器上。如果您在同一台服务器上同时运行 Varnish 和 Apache，则 Apache 需要在不同的端口上运行，例如端口 8080。