用magent+repcache搭建memcache集群和主备缓存

因为我们公司一直在用memcache,始终存在几个问题，问题如下：1、单点问题；2、缓存无备份和缓存无法同步问题。

针对以上问题给出具体的解决方案：

1、用magent，做集群和分布式。。

用magent，做集群和分布式。。
magent-0.5.tar.gz
libevent-1.4.14b-stable.tar.gz
memcached-1.4.25.tar.gz

memcached 的安装和依赖安装

1. 安装libevent

tar zxvf libevent-1.4.13-stable.tar.gz
cd libevent-1.4.13-stable
./configure --prefix=/usr/local/libevent-1.4.14
make
make install

2. 安装memcached

tar zxvf memcached-1.4.5.tar.gz
cd memcached-1.4.5.tar.gz
./configure --with-libevent=/usr/local/libevent-1.4.14 ## configure
需要加 libevent的安装路径世纪安装路径或者在当前路径下用yum install libevent来安装
make
make install
安装完成后配置路径
/usr/bin/install -c 'memcached' '/usr/local/bin/memcached'
配置memcached的路径
/usr/bin/install -c 'memcached-debug''/usr/local/bin/memcached-debug'
配置memcached-debug的路径

安装magent

mkdir magent
tar zxvfmagent-0.5.tar.gz -C magent
/sbin/ldconfig
sed -i "s#LIBS =-levent#LIBS = -levent -lm#g" Makefile
make
cp magent/usr/local/bin/magent

cd ../

/usr/local/bin/memcached -d -u kssadmin -p 11211
/usr/local/bin/memcached -d -u kssadmin -p 11212
/usr/local/bin/memcached -d -u kssadmin -p 11213

/usr/local/bin/magent-u root -d
-l 192.168.20.122 -p 12000 -s 127.0.0.1:11211 -s127.0.0.1:11212 -b 127.0.0.1:11213

分别在127.0.0.1机器的11211，11212,11213端口启动3个Memcached进程，在12000端口开启magent代理程序

11211和11212为主Memcached，11213为备份Memcached；

2、 用repcache 主备来解决缓存备份和缓存同步问题

memcached-1.2.8-repcached-2.2.tar

repcached下载地址：http://downloads.sourceforge.net/repcached

参考网上的例子自己安装repcache，安装过程中遇到各种问题一一解决并做了整理，并分享出来；首先感谢前人整理分享的资料，其次希望该资料给其他人带来方便。

具体代码：

# cd /home/kssadmin 进入到当前用户的主目录

#mkdir app 创建app

# mv /home/kssadmin/Desktop/ /home/kssadmin/app/ centos实在VM环境下搭建的，我从外部下载的安装包，并拷贝到Desktop中，移动到app下

#cd /home/kssadmin/app/

#ll

-rwxrwxrwx. 1 kssadmin kssadmin 227510 Jul 1 2014 memcached-1.2.8-repcached-2.2.tar.gz

准备工作已完成

#tar -zxvf memcached-1.2.8-repcached-2.2.tar.gz 解压缩

# cd memcached-1.2.8-repcached-2.2/

# yum install libevent-devel //用yum方式安装的libevent-devel 如果提示Another app is currently holding the yum lock; waiting for it to exit... 请参考后面解决方案

Loaded plugins: fastestmirror, langpacks

base | 3.6 kB 00:00

extras | 3.4 kB 00:00

jenkins | 951 B 00:00

updates | 3.4 kB 00:00

extras/7/x86_64/primary_db | 101 kB 00:00

jenkins/primary | 35 kB 00:01

Loading mirror speeds from cached hostfile

* base: mirror.bit.edu.cn

* extras: mirrors.neusoft.edu.cn

* updates: mirror.bit.edu.cn

jenkins 321/321

Resolving Dependencies

--> Running transaction check

---> Package libevent-devel.x86_64 0:2.0.21-4.el7 will be installed

--> Finished Dependency Resolution

Dependencies Resolved

================================================================================

Package Arch Version Repository Size

================================================================================

Installing:

libevent-devel x86_64 2.0.21-4.el7 base 85 k

Transaction Summary

================================================================================

Install 1 Package

Total download size: 85 k

Installed size: 357 k

Is this ok [y/d/N]: y

Downloading packages:

warning: /var/cache/yum/x86_64/7/base/packages/libevent-devel-2.0.21-4.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEY

Public key for libevent-devel-2.0.21-4.el7.x86_64.rpm is not installed

libevent-devel-2.0.21-4.el7.x86_64.rpm | 85 kB 00:03

Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Importing GPG key 0xF4A80EB5:

Userid : "CentOS-7 Key (CentOS 7 Official Signing Key) <security@centos.org>"

Fingerprint: 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5

Package : centos-release-7-1.1503.el7.centos.2.8.x86_64 (@anaconda)

From : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Is this ok [y/N]: y

Running transaction check

Running transaction test

Transaction test succeeded

Running transaction

Installing : libevent-devel-2.0.21-4.el7.x86_64 1/1

Verifying : libevent-devel-2.0.21-4.el7.x86_64 1/1

Installed:

libevent-devel.x86_64 0:2.0.21-4.el7

Complete! -----到此libebvent-devel 安装成功

# ./configure --enable-replication --program-transform-name=s/memcached/repcached/ 配置和生成makefle 文件

checking build system type... x86_64-unknown-linux-gnu

checking host system type... x86_64-unknown-linux-gnu

checking target system type... x86_64-unknown-linux-gnu

checking for a BSD-compatible install... /usr/bin/install -c

checking whether build environment is sane... yes

checking for a thread-safe mkdir -p... /usr/bin/mkdir -p

..................

#make

###make过程中如果约到一下问题：请参考后面解决方案,亲自解决过了 贴出来跟大家分享一下。。

ed.c: In function 'add_iov’:

memcached.c:696:30: error: 'IOV_MAX’ undeclared (first use in this function)

if (m->msg_iovlen == IOV_MAX ||

^

memcached.c:696:30: note: each undeclared identifier is reported only once for each function it appears in

.....

# make install

......

到此安装完成，下面完成配置：

# /usr/bin/install -c 'memcached' '/usr/local/bin/repcached' 正常模式启动

# /usr/bin/install -c 'memcached-debug' '/usr/local/bin/repcached-debug' debug模式启动

[kssadmin@localhost memcached-1.2.8-repcached-2.2]$ /usr/local/bin/repcached -p 11211 -v -d ######启动 占用端口 -p（-p <num> TCP port number to listen on (default:
11211)）指定端口 11211 -v (verbose (print errors/warnings while in event loop)) 打印错误信息和警告 -d 以守护进程方式启动 (run as a daemon )

replication: listen ## 显示当前信息证明启动成功

[kssadmin@localhost memcached-1.2.8-repcached-2.2]$ ps -ef|grep repchache ### 查看repchache 是否启动

kssadmin 3385 1 0 09:31 ? 00:00:01 /usr/bin/ibus-daemon --replace --xim --panel disable

kssadmin 9613 1 0 09:49 ? 00:00:00 /usr/local/bin/repcached -p 11211 -v -d

kssadmin 9683 3821 0 09:50 pts/0 00:00:00 grep --color=auto rep

/usr/local/bin/repcached -p 11212 -x 127.0.0.1 -v -d 启动备份

replication: connect (peer=127.0.0.1:11212)

replication: marugoto copying

replication: accept

[kssadmin@localhost memcached-1.2.8-repcached-2.2]$ replication: start

[kssadmin@localhost memcached-1.2.8-repcached-2.2]$ ps -aux

。。。

kssadmin 9613 0.0 0.0 9564 776 ? Ss 09:49 0:00 /usr/local/bin/repcached -p 11211 -v -d

kssadmin 9708 0.0 0.0 9516 580 ? Ss 09:50 0:00 /usr/local/bin/repcached -p 11212 -x 127.0.0.1 -v -d

。。。。

repcache启动成功

测试数据是否同步 首先telnet 11211 并写入数据

[root@localhost Packages]# telnet localhost 11211

Trying ::1...

Connected to localhost.

Escape character is '^]'.

set seven 0 0 8 注意：最后一位给出的是字符穿个数，输入的字符串位数必须够，否则会爆出错误：CLIENT_ERROR bad data chunk 这是因为存储的字节长度与指定的长度不匹配造成的

dddddddd

STORED

get seven

VALUE seven 0 8

dddddddd

END

quit

Connection closed by foreign host.

[root@localhost Packages]# telnet localhost 11212 -- 在备份的cache中取数据

Trying ::1...

Connected to localhost.

Escape character is '^]'.

get seven

VALUE seven 0 8

dddddddd

END

其次测试在备分缓存集成中写入数据是否会同步到主缓存中

[root@localhost Packages]# telnet localhost 11212

Trying ::1...

Connected to localhost.

Escape character is '^]'.

set back 0 0 6

------

STORED

get back

VALUE back 0 6

------

END

quit

Connection closed by foreign host.

[root@localhost Packages]# telnet localhost 11211

Trying ::1...

Connected to localhost.

Escape character is '^]'.

get back

VALUE back 0 6

------

END

quit

Connection closed by foreign host.

# yum install libevent-devel //用yum方式安装的libevent-devel

安装过过程中一直遇到如下问题，提示app被锁了，另外京城在占用这，如果遇到了可以选择杀掉 的进程或者直接结束上一次操作直接执行 rm -f /var/run/yum.pid

Loaded plugins: fastestmirror, langpacks

Existing lock /var/run/yum.pid: another copy is running as pid 4497.

Another app is currently holding the yum lock; waiting for it to exit...

The other application is: PackageKit

Memory : 132 M RSS (1.4 GB VSZ)

Started: Wed Feb 24 09:34:01 2016 - 04:48 ago

State : Sleeping, pid: 4497

Another app is currently holding the yum lock; waiting for it to exit...

The other application is: PackageKit

Memory : 132 M RSS (1.4 GB VSZ)

Started: Wed Feb 24 09:34:01 2016 - 04:50 ago

State : Sleeping, pid: 4497

Another app is currently holding the yum lock; waiting for it to exit...

The other application is: PackageKit

Memory : 132 M RSS (1.4 GB VSZ)

Started: Wed Feb 24 09:34:01 2016 - 04:52 ago

State : Sleeping, pid: 4497

#make

make && make install

提示编译出错：

make all-recursive

make[1]: Entering directory `/usr/local/memcached'

Making all in doc

make[2]: Entering directory `/usr/local/memcached/doc'

make[2]: Nothing to be done for `all'.

make[2]: Leaving directory `/usr/local/memcached/doc'

make[2]: Entering directory `/usr/local/memcached'

gcc -DHAVE_CONFIG_H -I. -DNDEBUG -m64 -g -O2 -MT memcached-memcached.o -MD

MP -MF .deps/memcached-memcached.Tpo -c -o memcached-memcached.o `test -f

memcached.c' || echo './'`memcached.c

memcached.c: In function 'add_iov’:

memcached.c:697: error: 'IOV_MAX’ undeclared (first use in this function)

memcached.c:697: error: (Each undeclared identifier is reported only once

memcached.c:697: error: for each function it appears in.)

make[2]: *** [memcached-memcached.o] Error 1

make[2]: Leaving directory `/usr/local/memcached'

make[1]: *** [all-recursive] Error 1

make[1]: Leaving directory `/usr/local/memcached'

make: *** [all] Error 2

解决方案：

vi memcached.c

将下面的几行

/* FreeBSD 4.x doesn't have IOV_MAX exposed. */

#ifndef IOV_MAX

#if defined(__FreeBSD__) || defined(__APPLE__)

# define IOV_MAX 1024

#endif

#endif

修改为

/* FreeBSD 4.x doesn't have IOV_MAX exposed. */

#ifndef IOV_MAX

# define IOV_MAX 1024

#endif

重新编译和安装：

make && make install