author：JevonWei

版权声明：原创作品

搭建NAT模式的HTTP环境

网络拓扑图如下



网络环境

RS1 192.168.198.138

RS2 192.168.198.120

LVS：

    DIP 192.168.198.128

    vip 172.16.253.105

路由R1：

    172.16.253.166

    192.168.80.128

Client 192.168.80.129

RS1,RS2的网关指向192.168.198.128，client的网关指向R1

实现NAT模式的轮询rr模式

VS

添加路由转发选项

[root@VS ~]# vim /etc/sysctl.d/99-sysctl.conf

    net.ipv4.ip_forward=1

[root@VS ~]# sysctl -p /etc/sysctl.d/99-sysctl.conf \\刷新生效

net.ipv4.ip_forward = 1

[root@VS ~]# route add  -net 192.168.80.0/24 gw 172.16.253.166

[root@VS ~]# route -n

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

0.0.0.0         192.168.198.1   0.0.0.0         UG    100    0        0 ens34

0.0.0.0         192.16.0.1      0.0.0.0         UG    101    0        0 ens33

172.16.0.0      0.0.0.0         255.255.0.0     U     100    0        0 ens33

192.16.0.1      0.0.0.0         255.255.255.255 UH    100    0        0 ens33

192.168.80.0    172.16.253.166  255.255.255.0   UG    0      0        0 ens33

192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0

192.168.198.0   0.0.0.0         255.255.255.0   U     100    0        0 ens34

配置LVS的调度算法为rr轮询

[root@VS ~]# yum -y install ipvsadm

[root@VS ~]# ipvsadm -A -t 172.16.253.105:80 -s rr \\-t指定TCP协议，-s指定调度算法为轮询

[root@VS ~]# ipvsadm -a -t 172.16.253.105:80 -r 192.168.198.138 -m \\添加192.168.198.138 RS1服务器到LVS调度，-m 为nat类型

[root@VS ~]# ipvsadm -a -t 172.16.253.105:80 -r 192.168.198.120 -m

[root@VS ~]# ipvsadm -Ln \\查看LVS调度信息

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:80 rr

  -> 192.168.198.120:80           Masq    1      0          0

  -> 192.168.198.138:80           Masq    1      0          0

[root@VS ~]# curl 192.168.198.120

welcome to RS2

[root@VS ~]# curl 192.168.198.138

welcome to RS1

修改LVS的调度模式为wrr

[root@VS ~]# ipvsadm -E -t 172.16.253.105:80 -s wrr

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:80 wrr

  -> 192.168.198.120:80           Masq    1      0          0

  -> 192.168.198.138:80           Masq    1      0          0

[root@VS ~]# ipvsadm -e -t 172.16.253.105:80 -r 192.168.198.138 -m -w 3 \\修改192.168.198.138 RS1主机的权重为3，-w 指定权重，-m为nat算法，192.168.198.120权重仍为1

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:80 wrr

  -> 192.168.198.120:80           Masq    1      0          0

  -> 192.168.198.138:80           Masq    3      0          0 

脚本实现lvs-wrr的配置

[root@VS ~]# vim lvs_nat.sh

#! /bin/bash

vip=172.16.253.105:80

rip1=192.168.198.138

rip2=192.168.198.120:8080

sch=wrr

case $1 in

start)

    ipvsadm -A -t $vip -s $sch

    ipvsadm -a -t $vip -r $rip1 -m -w 3

    ipvsadm -a -t $vip -r $rip2 -m -w 1

    ;;

stop)

    ipvsadm -C

    ;;

*)

    echo "Usage:$(basename $0) start|stop"

    exit 1

    ;;

esac

RS1

[root@RS1 ~]# yum -y install httpd

[root@RS1 ~]# vim /var/www/html/index.html

    welcome to RS1

[root@RS1 ~]# service httpd start

RS2

[root@RS2 ~]# yum -y install httpd

[root@RS2 ~]# vim /var/www/html/index.html

    welcome to RS2

[root@RS2 ~]# service httpd start

路由器R1

[root@R1 ~]# vim /etc/sysctl.d/99-sysctl.conf

    net.ipv4.ip_forward=1

[root@R1 ~]# sysctl -p /etc/sysctl.d/99-sysctl.conf

net.ipv4.ip_forward = 1

[root@R1 ~]# route add -net 172.16.0.0/16 gw 172.16.253.105

或

[root@R1 ~]# vim /etc/sysconfig/network-scripts/route-eth0

    172.16.0.0/16 via 172.16.253.105

[root@R1 ~]# route -n

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

192.168.80.0    192.168.80.129  255.255.255.0   UG    0      0        0 eth1

192.168.80.0    0.0.0.0         255.255.255.0   U     1      0        0 eth1

172.16.0.0      172.16.253.105  255.255.0.0     UG    0      0        0 eth0

172.16.0.0      0.0.0.0         255.255.0.0     U     1      0        0 eth0

0.0.0.0         172.16.0.1      0.0.0.0         UG    0      0        0 eth0

client

[root@client ~]# route add -net 172.16.0.0/16 gw 192.168.80.128

访问rr轮询算法

[root@client ~]# for i in {1..10};do curl 172.16.253.105;sleep 1;done

welcome to RS2

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS2

访问wrr权重算法

[root@client ~]# for i in {1..10};do curl 172.16.253.105;sleep 1;done

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

查看LVS的信息

[root@VS ~]# ipvsadm -Ln --stats

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes

  -> RemoteAddress:Port

TCP  172.16.253.105:80                  29      158      139    10710    15609

  -> 192.168.198.120:80                 15       82       69     5554     7923

  -> 192.168.198.138:80                 14       76       70     5156     7686

[root@VS ~]# ipvsadm -Ln --connection \\查看网络连接数

[root@VS ~]# cut -d " " -f1 /var/log/httpd/access_log | sort -nr | uniq -c| sort -n \\查看网络连接

搭建NAT模式的HTTPS环境

在以上实验的基础上搭建HTTPS

  • 拓扑图

VS搭建CA服务端

[root@VS ~]# cat /etc/pki/tls/openssl.cnf \\查看证书的相关路径

[root@VS ~]# (umask 077;openssl genrsa -out /etc/pki/CA/private/cakey.pem 1024) \\生成私钥文件

Generating RSA private key, 1024 bit long modulus

.............++++++

.........++++++

e is 65537 (0x10001)

[root@VS ~]# cd /etc/pki/CA

[root@VS CA]# openssl req -new -x509 -key private/cakey.pem -out cacert.pem -days 1024 \\生成自签名证书

You are about to be asked to enter information that will be incorporated

into your certificate request.

What you are about to enter is what is called a Distinguished Name or a DN.

There are quite a few fields but you can leave some blank

For some fields there will be a default value,

If you enter '.', the field will be left blank.

-----

Country Name (2 letter code) [XX]:CN

State or Province Name (full name) []:henan

Locality Name (eg, city) [Default City]:zhengzhou

Organization Name (eg, company) [Default Company Ltd]:danran.com

Organizational Unit Name (eg, section) []:it

Common Name (eg, your name or your server's hostname) []:ca.danran.com

Email Address []:

[root@VS CA]# touch index.txt

[root@VS CA]# echo 00 > serial

RS1申请CA证书

[root@RS1 ~]# cd /etc/httpd/conf.d/

[root@RS1 conf.d]# (umask 077;openssl genrsa -out httpd.key 1024)

Generating RSA private key, 1024 bit long modulus

........++++++

...........++++++

e is 65537 (0x10001)

[[root@RS1 conf.d]# openssl req -new -key httpd.key -out httpd.csr -days 10

You are about to be asked to enter information that will be incorporated into your certificate request.

What you are about to enter is what is called a Distinguished Name or a DN.

There are quite a few fields but you can leave some blank

For some fields there will be a default value,

If you enter '.', the field will be left blank.

-----

Country Name (2 letter code) [XX]:CN

State or Province Name (full name) []:henan

Locality Name (eg, city) [Default City]:zhengzhou

Organization Name (eg, company) [Default Company Ltd]:danran.com

Organizational Unit Name (eg, section) []:it

Common Name (eg, your name or your server's hostname) []:ca.danran.com

Email Address []:

Please enter the following 'extra' attributes to be sent with your certificate request

A challenge password []:

An optional company name []:

[root@RS1 conf.d]# scp httpd.csr 192.168.198.128:/etc/pki/CA \\证书申请文件发送给CA服务端

CA服务端颁发证书

[root@VS CA]# openssl ca -in httpd.csr -out certs/httpd.crt -days 365

Using configuration from /etc/pki/tls/openssl.cnf

Check that the request matches the signature

Signature ok

Certificate Details:

    Serial Number: 1 (0x1)

    Validity

        Not Before: Aug 19 13:00:12 2017 GMT

        Not After : Aug 19 13:00:12 2018 GMT

    Subject:

        countryName               = CN

        stateOrProvinceName       = henan

        organizationName          = danran.com

        organizationalUnitName    = it

        commonName                = ca.danran.com

    X509v3 extensions:

        X509v3 Basic Constraints:

            CA:FALSE

        Netscape Comment:

            OpenSSL Generated Certificate

        X509v3 Subject Key Identifier:

            BB:DC:5C:85:69:2B:0A:41:98:3B:7F:3E:15:69:1D:2B:C3:81:3E:EF

        X509v3 Authority Key Identifier:

            keyid:91:15:B3:DB:2D:94:91:2E:12:87:26:ED:05:5E:08:78:E0:10:7C:F8

[root@VS CA]# scp certs/httpd.crt 192.168.198.138:/etc/httpd/conf.d \\将证书文件颁发给RS1申请者

[root@VS CA]# scp cacert.pem 192.168.198.138:/etc/httpd/conf.d     \\将CA服务端证书发送给申请者

RS1

[root@RS1 conf.d]# scp cacert.pem httpd.crt httpd.key 192.168.198.120:/etc/httpd/conf.d \\将RS1的证书、私钥及CA证书文件发送给RS2

[root@RS1 ~]# yum -y install mod_ssl

[root@RS1 ~]# vim /etc/httpd/conf.d/ssl.conf  \\修改如下证书私钥、证书文件及CA证书文件的存放路径

    SSLCertificateFile /etc/httpd/conf.d/httpd.crt

    SSLCertificateKeyFile /etc/httpd/conf.d/httpd.key

    SSLCACertificateFile /etc/httpd/conf.d/cacert.pem

    修改后如下所示

    #   Server Certificate:

    # Point SSLCertificateFile at a PEM encoded certificate.  If

    # the certificate is encrypted, then you will be prompted for a

    # pass phrase.  Note that a kill -HUP will prompt again.  A new

    # certificate can be generated using the genkey(1) command.

    SSLCertificateFile /etc/httpd/conf.d/httpd.crt

    #   Server Private Key:

    #   If the key is not combined with the certificate, use this

    #   directive to point at the key file.  Keep in mind that if

    #   you've both a RSA and a DSA private key you can configure

    #   both in parallel (to also allow the use of DSA ciphers, etc.)

    SSLCertificateKeyFile /etc/httpd/conf.d/httpd.key

    #   Server Certificate Chain:

    #   Point SSLCertificateChainFile at a file containing the

    #   concatenation of PEM encoded CA certificates which form the

    #   certificate chain for the server certificate. Alternatively

    #   the referenced file can be the same as SSLCertificateFile

    #   when the CA certificates are directly appended to the server

    #   certificate for convinience.

    #SSLCertificateChainFile /etc/pki/tls/certs/server-chain.crt

    #   Certificate Authority (CA):

    #   Set the CA certificate verification path where to find CA

    #   certificates for client authentication or alternatively one

    #   huge file containing all of them (file must be PEM encoded)

    SSLCACertificateFile /etc/httpd/conf.d/cacert.pem

[root@RS1 conf.d]# service httpd restart

RS2

[root@RS2 ~]# cd /etc/httpd/conf.d/

[root@RS2 conf.d]# ls

cacert.pem  httpd.key       php.conf  welcome.conf

httpd.crt   mod_dnssd.conf  README

[root@RS2 conf.d]# yum -y install mod_ssl \\安装软件包

[root@RS2 conf.d]# vim ssl.conf \\修改如下证书私钥、证书文件及CA证书文件的存放路径

    SSLCertificateFile /etc/httpd/conf.d/httpd.crt

    SSLCertificateKeyFile /etc/httpd/conf.d/httpd.key

    SSLCACertificateFile /etc/httpd/conf.d/cacert.pem

    修改后如下所示

    #   Server Certificate:

    # Point SSLCertificateFile at a PEM encoded certificate.  If

    # the certificate is encrypted, then you will be prompted for a

    # pass phrase.  Note that a kill -HUP will prompt again.  A new

    # certificate can be generated using the genkey(1) command.

    SSLCertificateFile /etc/httpd/conf.d/httpd.crt

    #   Server Private Key:

    #   If the key is not combined with the certificate, use this

    #   directive to point at the key file.  Keep in mind that if

    #   you've both a RSA and a DSA private key you can configure

    #   both in parallel (to also allow the use of DSA ciphers, etc.)

    SSLCertificateKeyFile /etc/httpd/conf.d/httpd.key

    #   Server Certificate Chain:

    #   Point SSLCertificateChainFile at a file containing the

    #   concatenation of PEM encoded CA certificates which form the

    #   certificate chain for the server certificate. Alternatively

    #   the referenced file can be the same as SSLCertificateFile

    #   when the CA certificates are directly appended to the server

    #   certificate for convinience.

    #SSLCertificateChainFile /etc/pki/tls/certs/server-chain.crt

    #   Certificate Authority (CA):

    #   Set the CA certificate verification path where to find CA

    #   certificates for client authentication or alternatively one

    #   huge file containing all of them (file must be PEM encoded)

    SSLCACertificateFile /etc/httpd/conf.d/cacert.pem

[root@RS2 conf.d]# service httpd restart

VS

[root@VS ~]# vim lvs_nat.sh

#! /bin/bash

vip=172.16.253.105:443

rip1=192.168.198.138

rip2=192.168.198.120

sch=wrr

case $1 in

start)

    ipvsadm -A -t $vip -s $sch

    ipvsadm -a -t $vip -r $rip1 -m -w 3

    ipvsadm -a -t $vip -r $rip2 -m -w 1

    ;;

stop)

    ipvsadm -C

    ;;

*)

    echo "Usage:$(basename $0) start|stop"

    exit 1

    ;;

esac

[root@VS ~]# bash lvs_nat.sh stop

[root@VS ~]# bash lvs_nat.sh start

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:443 wrr

  -> 192.168.198.120:443          Masq    1      0          0

  -> 192.168.198.138:443          Masq    3      0          0

client客户端

[root@client ~]# for i in {1..10};do curl -k https://172.16.253.105;done  \\-k跳过证书

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

实现一个LVS调用一组不同服务

VS

搭建https的LVS_nat

[root@VS ~]# vim lvs_nat.sh

#! /bin/bash

vip=172.16.253.105:443

rip1=192.168.198.138

rip2=192.168.198.120

sch=wrr

case $1 in

start)

    ipvsadm -A -t $vip -s $sch

    ipvsadm -a -t $vip -r $rip1 -m -w 3

    ipvsadm -a -t $vip -r $rip2 -m -w 1

    ;;

stop)

    ipvsadm -C

    ;;

*)

    echo "Usage:$(basename $0) start|stop"

    exit 1

    ;;

esac

[root@VS ~]# bash lvs_nat.sh stop

[root@VS ~]# bash lvs_nat.sh start

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:443 wrr

  -> 192.168.198.120:443          Masq    1      0          0

  -> 192.168.198.138:443          Masq    3      0          0

[root@VS ~]# bash lvs_nat.sh start

搭建http的LVS_nat

[root@VS ~]# vim lvs_nat2.sh

#! /bin/bash

vip=172.16.253.105:80

rip1=192.168.198.138

rip2=192.168.198.120:8080

sch=wrr

case $1 in

start)

    ipvsadm -A -t $vip -s $sch

    ipvsadm -a -t $vip -r $rip1 -m -w 3

    ipvsadm -a -t $vip -r $rip2 -m -w 1

    ;;

stop)

    ipvsadm -C

    ;;

*)

    echo "Usage:$(basename $0) start|stop"

    exit 1

    ;;

esac

[root@VS ~]# bash lvs_nat.sh stop

[root@VS ~]# bash lvs_nat.sh start

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

TCP  172.16.253.105:443 wrr

  -> 192.168.198.120:443          Masq    1      0          0

  -> 192.168.198.138:443          Masq    3      0          0

[root@VS ~]# bash lvs_nat2.sh start

[root@VS ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

  TCP  172.16.253.105:80 wrr

  -> 192.168.198.120:8080         Masq    1      0          0

  -> 192.168.198.138:80           Masq    3      0          0

  TCP  172.16.253.105:443 wrr

  -> 192.168.198.120:443          Masq    1      0          0

  -> 192.168.198.138:443          Masq    3      0          0

client

[root@client ~]# for i in {1..10};do curl -k https://172.16.253.105;done

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS2

[root@client ~]# for i in {1..10};do curl -k http://172.16.253.105;done

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

welcome to RS1

welcome to RS1

welcome to RS2

welcome to RS1

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