【Linux】【Services】【Project】Haproxy Keepalived Postfix实现邮件网关Cluster

1. 简介：

1.1. 背景：公司使用exchange服务器作为邮件服务器，但是使用Postfix作为邮件网关实现病毒检测，内容过滤，反垃圾邮件等功能。原来的架构非常简单，只有两台机器，一个负责进公司的邮件，一个负责发公司到外部的邮件。由于公司人员增长迅速，再加上机房的迁移，原来的架构已经不能满足公司现有需要，需要重新设计一套邮件网关系统。

1.2. 基础概念：

1.2.1. postfix

1.2.2. haproxy:

1.2.3. keepalived:

1.2.4. clamav:

1.2.5. amavisd:

1.2.6. spamassassin:

1.2.7. SPF:

2. 环境：

2.1. OS: Red Hat Enterprise Linux Server release 7.3 (Maipo)

2.2. Kernel: 3.10.0-514.2.2.el7.x86_64

2.3. Haproxy: 1.5.18-3.el7_3.1

2.4. keepalived: 1.2.13-8.el7

2.5. 服务器

Server Name	IP	Software Installed	Comments
HCWHMAILPROXY01	10.25.8.2	postfix, amavisd,clamd,spamassassin,spf
HCWHMAILPROXY02	10.25.8.3	postfix, amavisd,clamd,spamassassin,spf
HCWHMAILPROXY03	10.25.8.4	postfix, amavisd,clamd,spamassassin,spf
HCWHMAILPROXY04	10.25.8.5	postfix, amavisd,clamd,spamassassin,spf
HCWHMAILDR01	10.25.2.45	haproxy
HCWHMAILDR01	10.25.2.22	keepalived	VIP
HCWHMAILDR02	10.25.2.46	haproxy
HCWHMAILDR02	10.25.2.23	keepalived	VIP

2.6. 网络信息

name	IP	Software	Managed by	Comments
F5		F5	Network	need DNS name and IP from outbound
lease line			Network
DNS	10.24.2.1	bind	Run Linux	resolve mailproxy.homecredit.cn to 10.25.2.22/23

3. 安装：

3.1. 调度器hcwhmaildr01/02, 配置好yum源之后可以直接安装

#直接安装就可以

[root@hcwhmaildr01 ~]# yum install keepalived haproxy -y

#记得开机启动并测试一下是否可以默认启动

[root@hcwhmaildr01 ~]# systemctl enable keepalived.service

Created symlink from /etc/systemd/system/multi-user.target.wants/keepalived.service to /usr/lib/systemd/system/keepalived.service.

[root@hcwhmaildr01 ~]# systemctl start keepalived.service

[root@hcwhmaildr01 ~]# systemctl enable haproxy.service

Created symlink from /etc/systemd/system/multi-user.target.wants/haproxy.service to /usr/lib/systemd/system/haproxy.service.

[root@hcwhmaildr01 ~]# systemctl start haproxy.service

[root@hcwhmaildr01 ~]#

keepalive配置文件 hcwhmaildr01

global_defs {

   notification_email {

     linux@homecredit.cn

   }

   notification_email_from zabbix@homecredit.cn

   smtp_server smtp.homecredit.cn

   smtp_connect_timeout 30

   router_id LVS_DEVEL

}

vrrp_script check_haproxy {

script "killall -0 haproxy"

        interval 1

        weight 21

}

vrrp_script chk_mantaince_down {

   script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0"

   interval 1

   weight 2

}

vrrp_instance VI_22 {

    state MASTER

    interface ens192

    virtual_router_id 22

    garp_master_delay 1

    mcast_src_ip 10.25.2.45

    lvs_sync_daemon_interface ens192

    priority 110

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_interface {

    ens192

    }

    virtual_ipaddress {

        10.25.2.22/24 dev ens192 label ens192:0

    }

    track_script {

    check_haproxy

    chk_mantaince_down

    }

}

vrrp_instance VI_23 {

    state BACKUP

    interface ens192

    virtual_router_id 23

    garp_master_delay 1

    mcast_src_ip 10.25.2.45

    lvs_sync_daemon_interface ens192

    priority 100

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_interface {

        ens192

    }

    virtual_ipaddress {

        10.25.2.23/24 dev ens192 label ens192:1

    }

    track_script {

    check_haproxy

    chk_mantaince_down

    }

}

[root@hcwhmaildr01 ~]# cat /etc/keepalived/keepalived.conf

keepalive配置文件 hcwhmaildr02

global_defs {

   notification_email {

     linux@homecredit.cn

   }

   notification_email_from zabbix@homecredit.cn

   smtp_server smtp.homecredit.cn

   smtp_connect_timeout 30

   router_id LVS_DEVEL

}

vrrp_script check_haproxy {

script "killall -0 haproxy"

        interval 1

        weight 21

}

vrrp_script chk_mantaince_down {

   script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0"

   interval 1

   weight 2

}

vrrp_instance VI_22 {

    state BACKUP

    interface ens192

    virtual_router_id 22

    garp_master_delay 1

    mcast_src_ip 10.25.2.46

    lvs_sync_daemon_interface ens192

    priority 100

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_interface {

    ens192

    }

    virtual_ipaddress {

        10.25.2.22/24 dev ens192 label ens192:0

    }

    track_script {

    check_haproxy

    chk_mantaince_down

    }

}

vrrp_instance VI_23 {

    state MASTER

    interface ens192

    virtual_router_id 23

    garp_master_delay 1

    mcast_src_ip 10.25.2.46

    lvs_sync_daemon_interface ens192

    priority 110

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1111

    }

    track_interface {

        ens192

    }

    virtual_ipaddress {

        10.25.2.23/24 dev ens192 label ens192:1

    }

    track_script {

    check_haproxy

    chk_mantaince_down

    }

}

[root@hcwhmaildr02 ~]# cat /etc/keepalived/keepalived.conf

haproxy配置文件 hcwhmaildr01

global

    log         127.0.0.1 local3

    chroot      /var/lib/haproxy

    pidfile     /var/run/haproxy.pid

    maxconn     4000

    user        haproxy

    group       haproxy

    daemon

    stats socket /var/lib/haproxy/stats

defaults

    mode                    http

    log                     global

    option                  httplog

    option                  dontlognull

    option http-server-close

    option forwardfor       except 127.0.0.0/8

    option                  redispatch

    retries                 3

    timeout http-request    10s

    timeout queue           1m

    timeout connect         10s

    timeout client          1m

    timeout server          1m

    timeout http-keep-alive 10s

    timeout check           10s

    maxconn                 3000

listen smtp *:25

    mode    tcp

    balance     roundrobin

    server  hcwhmailproxy01 10.25.8.2:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy02 10.25.8.3:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy03 10.25.8.4:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy04 10.25.8.5:25 weight 1 maxconn 10000 check inter 10s

listen stats *:9001

    stats enable

    stats uri /haproxyadmin?stats

    stats realm HAProxy\ Statistics

    stats auth admin:admin

    stats admin if TRUE

[root@hcwhmaildr01 ~]# cat /etc/haproxy/haproxy.cfg|grep -v "^#\|^.*#\|^$"

haproxy配置文件 hcwhmaildr02

global

    log         127.0.0.1 local3

    chroot      /var/lib/haproxy

    pidfile     /var/run/haproxy.pid

    maxconn     4000

    user        haproxy

    group       haproxy

    daemon

    stats socket /var/lib/haproxy/stats

defaults

    mode                    http

    log                     global

    option                  httplog

    option                  dontlognull

    option http-server-close

    option forwardfor       except 127.0.0.0/8

    option                  redispatch

    retries                 3

    timeout http-request    10s

    timeout queue           1m

    timeout connect         10s

    timeout client          1m

    timeout server          1m

    timeout http-keep-alive 10s

    timeout check           10s

    maxconn                 3000

listen smtp *:25

    mode    tcp

    balance     roundrobin

    server  hcwhmailproxy01 10.25.8.2:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy02 10.25.8.3:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy03 10.25.8.4:25 weight 1 maxconn 10000 check inter 10s

    server  hcwhmailproxy04 10.25.8.5:25 weight 1 maxconn 10000 check inter 10s

listen stats *:9001

    stats enable

    stats uri /haproxyadmin?stats

    stats realm HAProxy\ Statistics

    stats auth admin:admin

    stats admin if TRUE

[root@hcwhmaildr02 ~]# cat /etc/haproxy/haproxy.cfg|grep -v "^#\|^.*#\|^$"

3.2 postfix,amavisd-new, clamav, spamassassin, spf(python和perl版本的我都装上了)，还有qshape命令postfix-perl-scripts

yum install perl-Mail-SPF,python-pyspf,postfix, spamassassin, clamav, amavisd-new, postfix-perl-scripts

/etc/postfix/mail.cf

alias_database = hash:/etc/aliases

alias_maps = hash:/etc/aliases

command_directory = /usr/sbin

config_directory = /etc/postfix

daemon_directory = /usr/libexec/postfix

data_directory = /var/lib/postfix

debug_peer_level = 2

debugger_command = PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin ddd $daemon_directory/$process_name $process_id

& sleep 5html_directory = no

inet_interfaces = all

inet_protocols = all

mail_owner = postfix

mailq_path = /usr/bin/mailq.postfix

manpage_directory = /usr/share/man

mydestination = $myhostname, localhost.$mydomain, localhost

newaliases_path = /usr/bin/newaliases.postfix

queue_directory = /var/spool/postfix

readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES

sample_directory = /usr/share/doc/postfix-2.10.1/samples

sendmail_path = /usr/sbin/sendmail.postfix

setgid_group = postdrop

unknown_local_recipient_reject_code = 550

# 主机设置

mydestination = $myhostname, localhost.$mydomain, localhost

mynetworks_style = subnet

# 立即响应

smtpd_error_sleep_time = 0s

# 邮件大小和邮箱大小限制10M、2G

message_size_limit = 10485760

mailbox_size_limit = 2097152000

show_user_unknown_table_name = no

# 队列超时限制 1天

bounce_queue_lifetime = 1d

maximal_queue_lifetime = 1d

#HCC configuration

myhostname = hcwumailproxy01.homecredit.cn

transport_maps = hash:/etc/postfix/transport

relay_domains = homecredit.cn, shenzhen.homecredit.cn, ppf.cn, homecreditcfc.cn, hctest.cn

mynetworks = 10.24.0.0/16, 10.25.0.0/16, 10.26.0.0/16, 10.27.0.0/16, 10.31.0.0/16, 127.0.0.0/8, 10.30.0.0/16, 10.65.

0.0/16, 10.64.0.0/16mydomain = homecredit.cn

myorigin = $mydomain

masquerade_domains = homecredit.cn

masquerade_exceptions = root

# SMTP 收件方限制

smtpd_recipient_restrictions =

        permit_mynetworks,

        permit_sasl_authenticated,

        reject_non_fqdn_hostname,

        reject_non_fqdn_sender,

        reject_non_fqdn_recipient,

        reject_unauth_destination,

        reject_unauth_pipelining,

        reject_invalid_hostname,

    check_recipient_access hash:/etc/postfix/recipient_access

    check_policy_service unix:private/policy-spf

# SMTP 发件方限制

smtpd_sender_restrictions = check_sender_access hash:/etc/postfix/sender_access

# Header Check

header_checks = regexp:/etc/postfix/header_checks

# mailbox limit

#message_size_limit = 67108846

#mailbox_size_limit = 1024000000

canonical_maps = hash:/etc/postfix/canonical

/etc/postfix/master.cf

#

# Postfix master process configuration file.  For details on the format

# of the file, see the master(5) manual page (command: "man 5 master").

#

# Do not forget to execute "postfix reload" after editing this file.

#

# ==========================================================================

# service type  private unpriv  chroot  wakeup  maxproc command + args

#               (yes)   (yes)   (yes)   (never) (100)

# ==========================================================================

smtp      inet  n       -       n       -       -       smtpd

#smtp      inet  n       -       n       -       1       postscreen

#smtpd     pass  -       -       n       -       -       smtpd

#dnsblog   unix  -       -       n       -       0       dnsblog

#tlsproxy  unix  -       -       n       -       0       tlsproxy

#submission inet n       -       n       -       -       smtpd

#  -o syslog_name=postfix/submission

#  -o smtpd_tls_security_level=encrypt

#  -o smtpd_sasl_auth_enable=yes

  -o receive_override_options=no_address_mappings

  -o content_filter=smtp-amavis:127.0.0.1:10024

#  -o smtpd_reject_unlisted_recipient=no

#  -o smtpd_client_restrictions=$mua_client_restrictions

#  -o smtpd_helo_restrictions=$mua_helo_restrictions

#  -o smtpd_sender_restrictions=$mua_sender_restrictions

#  -o smtpd_recipient_restrictions=permit_sasl_authenticated,reject

#  -o milter_macro_daemon_name=ORIGINATING

#smtps     inet  n       -       n       -       -       smtpd

#  -o syslog_name=postfix/smtps

#  -o smtpd_tls_wrappermode=yes

#  -o smtpd_sasl_auth_enable=yes

#  -o smtpd_reject_unlisted_recipient=no

#  -o smtpd_client_restrictions=$mua_client_restrictions

#  -o smtpd_helo_restrictions=$mua_helo_restrictions

#  -o smtpd_sender_restrictions=$mua_sender_restrictions

#  -o smtpd_recipient_restrictions=permit_sasl_authenticated,reject

#  -o milter_macro_daemon_name=ORIGINATING

#628       inet  n       -       n       -       -       qmqpd

pickup    unix  n       -       n       60      1       pickup

cleanup   unix  n       -       n       -       0       cleanup

qmgr      unix  n       -       n       300     1       qmgr

#qmgr     unix  n       -       n       300     1       oqmgr

tlsmgr    unix  -       -       n       1000?   1       tlsmgr

rewrite   unix  -       -       n       -       -       trivial-rewrite

bounce    unix  -       -       n       -       0       bounce

defer     unix  -       -       n       -       0       bounce

trace     unix  -       -       n       -       0       bounce

verify    unix  -       -       n       -       1       verify

flush     unix  n       -       n       1000?   0       flush

proxymap  unix  -       -       n       -       -       proxymap

proxywrite unix -       -       n       -       1       proxymap

smtp      unix  -       -       n       -       -       smtp

relay     unix  -       -       n       -       -       smtp

#       -o smtp_helo_timeout=5 -o smtp_connect_timeout=5

showq     unix  n       -       n       -       -       showq

error     unix  -       -       n       -       -       error

retry     unix  -       -       n       -       -       error

discard   unix  -       -       n       -       -       discard

local     unix  -       n       n       -       -       local

virtual   unix  -       n       n       -       -       virtual

lmtp      unix  -       -       n       -       -       lmtp

anvil     unix  -       -       n       -       1       anvil

scache    unix  -       -       n       -       1       scache

#

# ====================================================================

# Interfaces to non-Postfix software. Be sure to examine the manual

# pages of the non-Postfix software to find out what options it wants.

#

# Many of the following services use the Postfix pipe(8) delivery

# agent.  See the pipe(8) man page for information about ${recipient}

# and other message envelope options.

# ====================================================================

#

# maildrop. See the Postfix MAILDROP_README file for details.

# Also specify in main.cf: maildrop_destination_recipient_limit=1

#

#maildrop  unix  -       n       n       -       -       pipe

#  flags=DRhu user=vmail argv=/usr/local/bin/maildrop -d ${recipient}

#

# ====================================================================

#

# Recent Cyrus versions can use the existing "lmtp" master.cf entry.

#

# Specify in cyrus.conf:

#   lmtp    cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4

#

# Specify in main.cf one or more of the following:

#  mailbox_transport = lmtp:inet:localhost

#  virtual_transport = lmtp:inet:localhost

#

# ====================================================================

#

# Cyrus 2.1.5 (Amos Gouaux)

# Also specify in main.cf: cyrus_destination_recipient_limit=1

#

#cyrus     unix  -       n       n       -       -       pipe

#  user=cyrus argv=/usr/lib/cyrus-imapd/deliver -e -r ${sender} -m ${extension} ${user}

#

# ====================================================================

#

# Old example of delivery via Cyrus.

#

#old-cyrus unix  -       n       n       -       -       pipe

#  flags=R user=cyrus argv=/usr/lib/cyrus-imapd/deliver -e -m ${extension} ${user}

#

# ====================================================================

#

# See the Postfix UUCP_README file for configuration details.

#

#uucp      unix  -       n       n       -       -       pipe

#  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)

#

# ====================================================================

#

# Other external delivery methods.

#

#ifmail    unix  -       n       n       -       -       pipe

#  flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)

#

#bsmtp     unix  -       n       n       -       -       pipe

#  flags=Fq. user=bsmtp argv=/usr/local/sbin/bsmtp -f $sender $nexthop $recipient

#

#scalemail-backend unix -       n       n       -       2       pipe

#  flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store

#  ${nexthop} ${user} ${extension}

#

#mailman   unix  -       n       n       -       -       pipe

#  flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py

#  ${nexthop} ${user}

#

# spam/virus section

#

smtp-amavis  unix  -    -       y       -       2       smtp

 -o smtp_data_done_timeout=1200

 -o disable_dns_lookups=yes

 -o smtp_send_xforward_command=yes

127.0.0.1:10025 inet n  -       y       -       -       smtpd

 -o content_filter=

 -o smtpd_helo_restrictions=

 -o smtpd_sender_restrictions=

 -o smtpd_recipient_restrictions=permit_mynetworks,reject

 -o mynetworks=127.0.0.0/8

 -o smtpd_error_sleep_time=0

 -o smtpd_soft_error_limit=1001

 -o smtpd_hard_error_limit=1000

 -o receive_override_options=no_header_body_checks

 -o smtpd_helo_required=no

 -o smtpd_client_restrictions=

 -o smtpd_restriction_classes=

 -o disable_vrfy_command=no

 -o strict_rfc821_envelopes=yes

#

# SPF

#

policy-spf  unix  -       n       n       -       -       spawn

     user=nobody argv=/usr/libexec/postfix/policyd-spf

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