前沿知识点:
-
nginx负责负载均衡(反向代理)
-
msm(memcached session manager)负责缓存会话信息,从而实现会话保持
所需包:
-
nginx和memcached采用最新稳定版
-
tomcat版本需要与msm版本一致,这里采用tomcat7
-
msm包共计9个包,包名具体信息查看附件,msm的所有包放到$CATALINA_HOME/lib
配置过程:
nginx的配置信息如下-->
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
...
http {
...
upstream tomcat {
server node1:8080;
server node2:8080;
#这里具体使用什么算法,暂定,不过我觉得ip_hash不好,会造成负载不均衡
}
server {
...
location ~* ^
/testapp
{
proxy_pass http:
//tomcat
;
proxy_redirect off;
proxy_set_header X-real-ip $remote_addr;
proxy_set_header X-forwarded-
for
$proxy_add_x_forwarded_for;
proxy_set_header Host $host;
}
...
}
}
|
tomcat的配置信息如下-->
首先修改server.xml,在默认的host flag中添加context
1
2
3
4
5
6
7
8
9
10
11
12
13
|
...
<
host
>
...
<
context
path
=
"/testapp"
docbase
=
"testapp/"
/>
...
</
host
>
...
|
其次修改context.xml,在默认的context flag中添加manager
其中粘性session方式如下: Sticky 模式 : tomcat 本地容器 session 为 主 session , memcached 为备 session 。 Request 请求到来时, 判断tomcat容器是否发生变化,若变化(即原tomcat down掉),则 从 memcached 加载备 session 到 tomcat2 ,响应给客户端,请求结束后,重置session_id,并更新到memcached 。
1
2
3
4
5
6
7
8
9
|
<
Context
>
...
<
Manager
className
=
"de.javakaffee.web.msm.MemcachedBackupSessionManager"
memcachedNodes
=
"n1:host1.yourdomain.com:11211,n2:host2.yourdomain.com:11211"
failoverNodes
=
"n1"
requestUriIgnorePattern
=
".*\.(ico|png|gif|jpg|css|js)$"
transcoderFactoryClass
=
"de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
/>
</
Context
>
|
非粘性session如下: Non-Sticky 模式 : tomcat session 为 中转 session , memcached1 为主, memcached 2 为备 session 。 Request 请求到来时,从 memcached 2 加载备 session 到 tomcat ,(另外,若 只有一个 memcached 节点,或者 memcached2 出错时,且 tomcat本地 容器 中还没有 session, 则从 memcached1 加载主 session 到 tomcat ), Request 请求结束时,将 tomcat session 更新至 主 memcached1 和备 memcached2 ,并且清除 tomcat session 。以达到主备同步之目的,如下是non-sticky模式的响应流程图:(图片来源网络)。
此模式下,基于session的验证码将无法使用,因为此模式下,第一次session是用本地,然后存放到mem1和mem2中,之后客户再次请求,则路由到了另外一台tomcat上,又因为是同一个session_id,所以使用的是mem1中,但是mem1中确是旧的session.(但是验证码要求每一次都不一样...)
1
2
3
4
5
6
7
8
9
10
11
|
<
Context
>
...
<
ManagerclassName
=
"de.javakaffee.web.msm.MemcachedBackupSessionManager"
memcachedNodes
=
"n1:host1.yourdomain.com:11211,n2:host2.yourdomain.com:11211"
sticky
=
"false"
sessionBackupAsync
=
"false"
lockingMode
=
"uriPattern:/path1|/path2"
requestUriIgnorePattern
=
".*\.(ico|png|gif|jpg|css|js)$"
transcoderFactoryClass
=
"de.javakaffee.web.msm.serializer.kryo.KryoTranscoderFactory"
/>
</
Context
>
|
keepalived配置信息如下-->这里只贴出主的,从的就不贴了
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
! Configuration File
for
keepalived
global_defs {
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
#<Spinestars
vrrp_script chk_keepalived_down {
script
"[ -f /var/run/keepaliveddown ] && exit 1 || exit 0"
interval 2
weight -2
}
#nginx_check_script
vrrp_script chk_nginx {
script
"killall -0 nginx && exit 0 || exit 1"
interval 2
weight -2
}
#/Spinestars>
vrrp_instance VI_1 {
state MASTER
interface eth1
virtual_router_id 20
mcast_src_ip 192.168.100.1
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
10.88.100.2
}
track_script {
chk_nginx
chk_keepalived_down
}
}
|
nginx动静分离配置:
...
#<Spinestars
upstream tomcat_servers {
server node1
:
8080
;
server node2
:
8080
;
}
server {
listen
*
:
80
;
server_name
test
.shop.com;
root
/
var
/
www
/
shop;
index index.html index.jsp index.htm;
#/Spinestars>
#<Spinestars
location
~
*
\.(html
|
jpg
|
png
|
jpeg
|
css
|
gif
|
ico)$ {
root
/
var
/
www;
}
location
~
*
\.(js
|
jhtml)$ {
proxy_pass http
:
/
/
tomcat_servers;
proxy_redirect off;
proxy_set_header X
-
Forwarded
-
For $proxy_add_x_forwarded_for;
proxy_set_header Host $host;
proxy_set_header X
-
Real
-
IP $remote_addr;
}
if
( $host
=
'test.shop.com'
){
rewrite
^
/
$
http
:
/
/
test
.shop.com
/
shop
permanent;
}
#以下location是测试用的
location
~
*
^
/
testapp {
proxy_pass http
:
/
/
tomcat_servers;
proxy_redirect off;
proxy_set_header X
-
Forwarded
-
For $proxy_add_x_forwarded_for;
proxy_set_header Host $host;
proxy_set_header X
-
Real
-
IP $remote_addr;
}
#/Spinestars>
...
}