- 論壇徽章:
- 0
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LVS是中國(guó)人發(fā)起的項(xiàng)目，真是意外呀!大家可以看http://www.douzhe.com/linuxtips/1665.html
我是從最初的HA(高可用性)開(kāi)始的，別人的例子是用VMWARE，可以做試驗(yàn)但不能實(shí)際應(yīng)用，我又
沒(méi)有光纖卡的Share Storage，于是就選用ISCSI，成功后又發(fā)現(xiàn)ISCSI+EXT3不能用于LVS，倒最后發(fā)
現(xiàn)GFS可用，我最終成功配成可實(shí)際應(yīng)用的LVS，前后斷斷續(xù)續(xù)花了四個(gè)月，走了很多彎路。我花了
三天時(shí)間寫(xiě)下這篇文章，希望對(duì)大家有用。
這里要感謝linuxfans.org、linuxsir.com、chinaunix.com以及其它很多網(wǎng)站，很多資料都是從
他們的論壇上找到的。
參考文檔及下載點(diǎn)
a.http://www.gyrate.org/misc/gfs.txt
b.http://www.redhat.com/docs/manuals/enterprise/RHEL-3-Manual/cluster-suite/index.html
http://www.redhat.com/docs/manuals/csgfs/admin-guide/index.html
c.ftp://ftp.redhat.com/pub/redhat/linux/updates/enterprise/3ES/en/RHGFS/SRPMS
d.http://distro.ibiblio.org/pub/linux/distributions/caoslinux/centos/3.1/contrib/i386/RPMS/
LVS結(jié)構(gòu)圖：
eth0=10.3.1.101
eth0:1=10.3.1.254
Load Balance
Router
eth1=192.168.1.71
eth1:1=192.168.1.1
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Real1 Real2
eth0=192.168.1.68 eth0=192.168.1.67
(eth0 gateway=192.168.1.1)
eth1=192.168.0.1---eth1=192.168.0.2
(雙機(jī)互聯(lián)線)
|
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GFS
ISCSI
Share storage
eth0=192.168.1.124
1.Setup ISCSI Server
Server: PIII 1.4,512M, Dell 1650,Redhat 9,IP=192.168.1.124
從http://iscsitarget.sourceforge.net/下載ISCSI TARGET的Source code
(http://sourceforge.net/project/showfiles.php?group_id=108475&package_id=117141)
我選了iscsitarget-0.3.8.tar.gz,要求kernel 2.4.29
從kernel.org下載kernel 2.4.29,解開(kāi)編譯重啟后編譯安裝iscsitarget-0.3.8：
#make KERNELSRC=/usr/src/linux-2.4.29
#make KERNELSRC=/usr/src/linux-2.4.29 install
#cp ietd.conf /etc
#vi /etc/ietd.conf
# Example iscsi target configuration
#
# Everything until the first target definition belongs
# to the global configuration.
# Right now this is only the user configuration used
# during discovery sessions:
# Users, who can access this target
# (no users means anyone can access the target)
User iscsiuser 1234567890abc
Target iqn.2005-04.com.my:storage.disk2.sys1.iraw1
User iscsiuser 1234567890abc
Lun 0 /dev/sda5 fileio
Alias iraw1
Target iqn.2005-04.com.my:storage.disk2.sys1.iraw2
User iscsiuser 1234567890abc
Lun 1 /dev/sda6 fileio
Alias iraw2
Target iqn.2005-04.com.my:storage.disk2.sys2.idisk
User iscsiuser 1234567890abc
Lun 2 /dev/sda3 fileio
Alias idisk
Target iqn.2005-04.com.my:storage.disk2.sys2.icca
User iscsiuser 1234567890abc
Lun 3 /dev/sda7 fileio
Alias icca
說(shuō)明：password 長(zhǎng)度必須不小于12個(gè)字符, Alias是別名, 不知為何這個(gè)別名在
Client端顯示不出來(lái).
分區(qū)：我只有一個(gè)SCSI盤(pán)，所以：
/dev/sda3: Share storage,容量越大越好
/dev/sda5: raw1, 建Cluster要的rawdevice, 我給了900M
/dev/sda6: raw2, 建Cluster要的rawdevice, 我給了900M
/dev/sda7: cca, 建GFS要的,我給了64M
(/dev/sda4是Extended分區(qū),在其中建了sda5,6,7)
#Reboot，用service iscsi-target start啟ISCSI server(我覺(jué)得比建議的好，可以
用service iscsi-target status看狀態(tài))
2.Setup ISCSI Client(on two real server)
Server: PIII 1.4,512M, Dell 1650,Redhat AS3U4(用AS3U5更好),2.4.21-27.EL
#vi /etc/iscsi.conf
DiscoveryAddress=192.168.1.124
OutgoingUsername=iscsiuser
OutgoingPassword=1234567890abc
Username=iscsiuser
Password=1234567890abc
LoginTimeout=15
IncomingUsername=iscsiuser
IncomingPassword=1234567890abc
SendAsyncTest=yes
#service iscsi restart
#iscsi-ls -l
..., 精簡(jiǎn)如下:
/dev/sdb:iraw2
/dev/sdc:iraw1
/dev/sdd:idisk
/dev/sde:icca
注意: 在real server中ISCSI device的順序很重要，兩個(gè)real server中一定要一樣，如不一樣
就改ISCSI Server中的設(shè)置，多試幾次
3.Install Redhat Cluster suite
先下載Cluster Suite的ISO, AS3的我是從ChinaUnix.net找到的下載點(diǎn), 安裝clumanager和
redhat-config-cluster。沒(méi)有Cluster Suite的ISO也沒(méi)關(guān)系，從
ftp://ftp.redhat.com/pub/redhat/linux/updates/enterprise/3ES/en/RHCS/SRPMS/下載
clumanager-1.2.xx.src.rpm,redhat-config-cluster-1.0.x.src.rpm,編譯后安裝，應(yīng)該更好:
#rpm -Uvh clumanager-1.2.26.1-1.src.rpm
#rpmbuild -bs /usr/src/redhat/SPECS/clumanager.spec
#rpmbuild --rebuild --target i686 /usr/src/redhat/SRPMS/clumanager-1.2.26.1-1.src.rpm
還有redhat-config-cluster-1.0.x.src.rpm，也裝好
4.Setup Cluster as HA module
詳細(xì)步驟我就不寫(xiě)了，網(wǎng)上有很多文章，我也是看了別人的文章學(xué)會(huì)的，不過(guò)人家是用VMWARE，
而我是用真的機(jī)子+ISCSI，raw device就是/dev/sdb,/dev/sdc, 然后就
mount /dev/sdd /u01, mkfs.ext3 /u01 ......
設(shè)好后會(huì)發(fā)現(xiàn)ISCSI有問(wèn)題：同時(shí)只能有一個(gè)Client聯(lián)接寫(xiě)盤(pán)，如果
兩個(gè)Client同時(shí)聯(lián)ISCSI的Share Storge,一個(gè)Client寫(xiě)，另一個(gè)Client是看不到的，而且此時(shí)文
件系統(tǒng)已經(jīng)破壞了，Client重聯(lián)ISCSI時(shí)會(huì)發(fā)現(xiàn)文件是壞的，用fsck也修復(fù)不了。
ISCSI真的是雞肋嗎？
NO！從GOOGLE上我終于查到ISCSI只有用Cluster File System才能真正用于Share Storage!
而Redhat買(mǎi)下的GFS就是一個(gè)!
5.Setup GFS on ISCSI
GFS只有Fedora Core4才自帶了，而GFS又一定要用到Cluster Suite產(chǎn)生的/etc/cluster.xml文件，
我沒(méi)見(jiàn)FC4有Cluster Suite,真不知Redhat給FC4帶GFS干嘛，饞人嗎？
好，閑話少說(shuō)，下載：c處的GFS-6.0.2.20-2.src.rpm， 按a處的gfs.txt編譯安裝，不過(guò)關(guān)于
cluster.ccs,fence.ccs,nodes.ccs的設(shè)置沒(méi)說(shuō)，看b的文檔，我總算弄出來(lái)了，都存在
/root/cluster下，存在別的地方也行，不過(guò)我不知道有沒(méi)有錯(cuò)，我沒(méi)有光纖卡，文檔又沒(méi)講ISCSI
的例子，不過(guò)GFS能啟動(dòng)的。
#cat cluster.ccs
cluster {
name = "Cluster_1"
lock_gulm {
servers = ["cluster1", "cluster2"]
heartbeat_rate = 0.9
allowed_misses = 10
}
}
注：name就是Cluster Suite設(shè)置的Cluster name, servers就是Cluster member的Hostname，別忘
了加進(jìn)/etc/hosts;allowed_misses我開(kāi)始設(shè)為1，結(jié)果跑二天GFS就會(huì)死掉，改為10就沒(méi)死過(guò)了。
#cat fence.ccs
fence_devices{
admin {
agent = "fence_manual"
}
}
#cat nodes.ccs
nodes {
cluster1 {
ip_interfaces {
hsi0 = "192.168.0.1"
}
fence {
human {
admin {
ipaddr = "192.168.0.1"
}
}
}
}
cluster2 {
ip_interfaces {
hsi0 = "192.168.0.2"
}
fence {
human {
admin {
ipaddr = "192.168.0.2"
}
}
}
}
}
注：ip就是心跳線的ip
這三個(gè)文件建在/root/cluster下，先建立Cluster Configuration System：
a.#vi /etc/gfs/pool0.cfg
poolname pool0
minor 1 subpools 1
subpool 0 8 1 gfs_data
pooldevice 0 0 /dev/sde1
b.#pool_assemble -a pool0
c.#ccs_tool create /root/cluster /dev/pool/pool0
d.#vi /etc/sysconfig/gfs
CCS_ARCHIVE="/dev/pool/pool0"
再Creating a Pool Volume，就是我們要的共享磁盤(pán)啦，
a.#vi /etc/gfs/pool1.cfg
poolname pool1
minor 2 subpools 1
subpool 0 128 1 gfs_data
pooldevice 0 0 /dev/sdd1
b.#pool_assemble -a pool1
c.#gfs_mkfs -p lock_gulm -t Cluster_1:gfs1 -j 8 /dev/pool/pool1
d.#mount -t gfs -o noatime /dev/pool/pool1 /u01
下面是個(gè)GFS的啟動(dòng)腳本，注意real1和real2必須同時(shí)啟動(dòng)lock_gulmd進(jìn)程，第一臺(tái)lock_gulmd
會(huì)成為Server并等Client的lock_gulmd，幾十秒后沒(méi)有響應(yīng)會(huì)fail，GFS啟動(dòng)失敗。Redhat建議
GFS盤(pán)不要寫(xiě)進(jìn)/etc/fstab。
#cat gfstart.sh
#!/bin/sh
depmod -a
modprobe pool
modprobe lock_gulm
modprobe gfs
sleep 5
service iscsi start
sleep 20
service rawdevices restart
pool_assemble -a pool0
pool_assemble -a pool1
service ccsd start
service lock_gulmd start
mount -t gfs /dev/pool/pool1 /s02 -o noatime
service gfs status
6. Setup Linux LVS
LVS是章文嵩博士發(fā)起和領(lǐng)導(dǎo)的優(yōu)秀的集群解決方案，許多商業(yè)的集群產(chǎn)品，比如RedHat的
Piranha，Turbolinux公司的Turbo Cluster等，都是基于LVS的核心代碼的。
我的系統(tǒng)是Redhat AS3U4，就用Piranha了。
從rhel-3-u5-rhcs-i386.iso安裝piranha-0.7.10-2.i386.rpm,ipvsadm-1.21-9.ipvs108.i386.rpm
(http://distro.ibiblio.org/pub/linux/distributions/caoslinux/centos/3.1/contrib/i386/RPMS/)
裝完后service httpd start & service piranha-gui start，就可以從http://xx.xx.xx.xx:3636管理或
設(shè)置了，當(dāng)然了，手工改/etc/sysconfig/ha/lvs.cf也一樣。
#cat /etc/sysconfig/ha/lvs.cf
serial_no = 80
primary = 10.3.1.101
service = lvs
rsh_command = ssh
backup_active = 0
backup = 0.0.0.0
heartbeat = 1
heartbeat_port = 1050
keepalive = 6
deadtime = 18
network = nat
nat_router = 192.168.1.1 eth1:1
nat_nmask = 255.255.255.0
reservation_conflict_action = preempt
debug_level = NONE
virtual lvs1 {
active = 1
address = 10.3.1.254 eth0:1
vip_nmask = 255.255.255.0
fwmark = 100
port = 80
persistent = 60
pmask = 255.255.255.255
send = "GET / HTTP/1.0\r\n\r\n"
expect = "HTTP"
load_monitor = ruptime
scheduler = wlc
protocol = tcp
timeout = 6
reentry = 15
quiesce_server = 1
server Real1 {
address = 192.168.1.68
active = 1
weight = 1
}
server Real2 {
address = 192.168.1.67
active = 1
weight = 1
}
}
virtual lvs2 {
active = 1
address = 10.3.1.254 eth0:1
vip_nmask = 255.255.255.0
port = 21
send = "\n"
use_regex = 0
load_monitor = ruptime
scheduler = wlc
protocol = tcp
timeout = 6
reentry = 15
quiesce_server = 0
server ftp1 {
address = 192.168.1.68
active = 1
weight = 1
}
server ftp2 {
address = 192.168.1.67
active = 1
weight = 1
}
}
設(shè)置完后service pulse start, 別忘了把相關(guān)的client加進(jìn)/etc/hosts
#iptables -t mangle -A PREROUTING -p tcp -d 10.3.1.254/32 --dport 80 -j MARK --set-mark 100
#iptables -t mangle -A PREROUTING -p tcp -d 10.3.1.254/32 --dport 443 -j MARK --set-mark 100
#iptables -A POSTROUTING -t nat -p tcp -s 10.3.1.0/24 --sport 20 -j MASQUERADE
運(yùn)行以上三行命令并存入/etc/rc.d/rc.local，用ipvsadm看狀態(tài)：
#ipvsadm
IP Virtual Server version 1.0.8 (size=65536)
Prot LocalAddress ort Scheduler Flags
->; RemoteAddressort Forward Weight ActiveConn InActConn
TCP 10.3.1.254:ftp wlc
->; cluster2:ftp Masq 1 0 0
->; cluster1:ftp Masq 1 0 0
FWM 100 wlc persistent 60
->; cluster1:0 Masq 1 0 0
->; cluster2:0 Masq 1 0 0
注意：a.Firewall Mark可以不要，我反正是加了，文檔說(shuō)有https的話加上，值我選了100，
b.Virtual IP別加進(jìn)/etc/hosts，我上過(guò)當(dāng)，80端口時(shí)有時(shí)無(wú)的，
c.eth0:1,eth1:1是piranha產(chǎn)生的，別自己手工設(shè)置，我干過(guò)這畫(huà)蛇添足的事，網(wǎng)上有
些帖子沒(méi)說(shuō)清，最后是看Redhat的文檔才弄清楚的。
d.The LVS router can monitor the load on the various real servers by using
either rup or ruptime. If you select rup from the drop-down menu, each real
server must run the rstatd service. If you select ruptime, each real server
must run the rwhod service.Redhat的原話，就是如選rup的監(jiān)控模式real server上
都要運(yùn)行rstatd進(jìn)程，如選ruptime就要運(yùn)行rwhod進(jìn)程。
e.Real Server同Router相聯(lián)的網(wǎng)卡的Gateway必須是Router的那塊網(wǎng)卡的VIP，舉本例：
Router的eth1同兩個(gè)real server的eth0相聯(lián)，如VIP eth1:1=192.168.1.1，則real
server 的eth0的Gateway=192.168.1.1
7.Setup TOMCAT5.59+JDK1.5(用Redhat自帶的Apache)
a.#tar xzvf jakarta-tomcat-5.5.9.tar.gz
#mv jakarta-tomcat-5.5.9 /usr/local
#ln -s /usr/local/jakarta-tomcat-5.5.9 /usr/local/tomcat
b.#jdk-1_5_0_04-linux-i586.bin
#mv jdk1.5.0_4 /usr/java
#ln -s /usr/java/jdk1.5.0_4 /usr/java/jdk
c.#vi /etc/profile.d/tomcat.sh
export CATALINA_HOME=/usr/local/tomcat
export TOMCAT_HOME=/usr/local/tomcat
d.#vi /etc/profile.d/jdk.sh
if ! echo ${PATH} | grep "/usr/java/jdk/bin" ; then
JAVA_HOME=/usr/java/jdk
export JAVA_HOME
export PATH=/usr/java/jdk/bin {PATH}
export CLASSPATH=$JAVA_HOME/lib
fi
e.#chmod 755 /etc/profile.d/*.sh
f.重新用root登錄，讓tomcat.sh和jdk.sh起作用，
#tar xzvf jakarta-tomcat-connectors-jk2-src-current.tar.gz
#cd jakarta-tomcat-connectors-jk2-2.0.4-src/jk/native2/
#./configure --with-apxs2=/usr/sbin/apxs --with-jni --with-apr-lib=/usr/lib
#make
#libtool --finish /usr/lib/httpd/modules
#cp ../build/jk2/apache2/mod_jk2.so ../build/jk2/apache2/libjkjni.so /usr/lib/httpd/modules/
g.#vi /usr/local/tomcat/bin/catalina.sh
在# Only set CATALINA_HOME if not already set后加上以下兩行：
serverRoot=/etc/httpd
export serverRoot
h.#vi /usr/local/tomcat/conf/jk2.properties
serverRoot=/etc/httpd
apr.NativeSo=/usr/lib/httpd/modules/libjkjni.so
apr.jniModeSo=/usr/lib/httpd/modules/mod_jk2.so
i.#vi /usr/local/tomcat/conf/server.xml,
在</Host>;前加上以下幾行，建了兩個(gè)VirtualPath：myjsp和local，一個(gè)指向share storage，
一個(gè)指向real server本地
<Context path="/myjsp" docBase="/u01/www/myjsp" debug="0"/>;
<Logger className="org.apache.catalina.logger.FileLogger" directory="/var/log/httpd"
prefix="cluster.log." suffix=".txt" timestamp="true" />;
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="/var/log/httpd"
prefix="cluster_access.log." suffix=".txt" pattern="common" resolveHosts="false" />;
<Context path="/local" docBase="/var/www/html" debug="1" reloadable="true" crossContext="true" />;
j.#vi /etc/httpd/conf/workers2.properties
#[logger.apache2]
#level=DEBUG
[shm]
file=/var/log/httpd/shm.file
size=1048576
[channel.socket]
tomcatId=localhost:8009
keepalive=1
info=Ajp13 forwarding over socket
[ajp13]
channel=channel.socket:localhost:8009
[status]
info=Status worker, displays runtime informations
[uri:/*.jsp]
worker=ajp13:localhost:8009
context=/
k.#vi /etc/httpd/conf/httpd.conf
改 ocumentRoot "/u01/www"
加：
在LoadModule最后加：
LoadModule jk2_module modules/mod_jk2.so
JkSet config.file /etc/httpd/conf/workers2.properties
在#<VirtualHost *>;之前加：
<Directory ~ "/WEB-INF/">;
Order allow,deny
Deny from all
</Directory>;
l:#mkdir /u01/ftproot
#mkdir /u01/www
#mkdir /u01/www/myjsp
m:在每個(gè)real server上生成index.jsp
#vi /var/www/html/index.jsp
<%@ page import="java.util.*,java.sql.*,java.text.*" contentType="text/html"
%>;
<%
out.println("test page on real server 1" ;
%>;
在real server2上就是"test page on real server 2"
n:下載jdbc Driver
http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/htdocs/jdbc9201.html
可惜只有for JDK1.4的,在兩臺(tái)real server上分別
#cp -R /usr/local/tomcat/webapps/webdav/WEB-INF /u01/www/myjsp
#cp ojdbc14.jar ojdbc14_g.jar ocrs12.zip /u01/www/myjsp/WEB-INF/lib
o:假設(shè)我有一臺(tái)OracleServer，ip=10.3.1.211,sid=MYID,username=my,password=1234,并有Oracle
的例子employees的read權(quán)限,或干脆把這個(gè)table拷過(guò)來(lái),我是Oracle9i中的
#vi /u01/www/myjsp/testoracle.jsp
<%@ page contentType="text/html" %>;
<%@ page import="java.sql.*"%>;
<?xml version="1.0"?>;
<html">;
<head>;
<meta http-equiv="Content-Type" content="text/html" />;
<title>;Test ORACLE Employees</title>;
</head>;
<body>;
<%
String OracleDBDriver="oracle.jdbc.driver.OracleDriver";
String DBUrl="jdbc racle:thin 10.3.1.211:1521:MYID";
String UserID="my";
String UserPWD="1234";
Connection conn=null;
Statement stmt=null;
ResultSet rs=null;
try
{
Class.forName(OracleDBDriver);
}
catch(ClassNotFoundException ex)
{
System.out.println("Class.forname:"+ex);
}
conn=DriverManager.getConnection(DBUrl,UserID,UserPWD);
stmt=conn.createStatement();
String sql="select * from EMPLOYEES";
rs = stmt.executeQuery(sql);
out.print("<table border>;";
out.print("<tr>;";
out.print("<th width=100>;"+"EMPLOYEE_ID";
out.print("<th width=50>;"+"FIRST_NAME";
out.print("<th width=50>;"+"LAST_NAME";
out.print("<th width=50>;"+"EMAIL";
out.print("<th width=50>;"+" HONE_NUMBER";
out.print("<th width=50>;"+"HIRE_DATE";
out.print("<th width=50>;"+"JOB_ID";
out.print("<tr>;");
try
{
while(rs.next())
{
out.print("<tr>;");
int n=rs.getInt(1);
out.print("<td>;"+n+"</td>;");
String e=rs.getString(2);
out.print("<td>;"+e+"</td>;");
//String e=rs.getString(3);
out.print("<td>;"+rs.getString(3)+"</td>;");
out.print("<td>;"+rs.getString(4)+"</td>;");
out.print("<td>;"+rs.getString(5)+"</td>;");
out.print("<td>;"+rs.getString(6)+"</td>;");
out.print("<td>;"+rs.getString(7)+"</td>;");
out.print("</tr>;");
}
}
catch(SQLException ex)
{
System.err.println("ConnDB.Main:"+ex.getMessage());
}
out.print("</table>;");
rs.close();
stmt.close();
conn.close();
%>;
</body>;
</html>;
p:#vi /u01/www/index.html
<p>;
<META HTTP-EQUIV="Refresh" CONTENT="10; URL=http://10.3.1.254/myjsp/testoracle.jsp">;
</BODY>;
<p>;
<a href="http://10.3.1.254/local/index.jsp">;WEB Local</a>;
<p>;
<a href="http://10.3.1.254/myjsp/testoracle.jsp">;Test Oracle WEB</a>;
</HTML>;
q:在兩臺(tái)real server上分別
#vi /usr/local/tomcat/conf/tomcat-users.xml
加下面一行，允許頁(yè)面管理：
<user username="manager" password="tomcat" roles="manager"/>;
r:在兩臺(tái)real server上分別
#service httpd restart
#/usr/local/tomcat/bin/startup.sh
s:打開(kāi)http://1092.168.1.68:8080和http://1092.168.1.67:8080，選Tomcat Manager，用
manager/tomcat登錄，虛擬目錄/myjsp和/local應(yīng)該Start了
在兩臺(tái)機(jī)子上分別打開(kāi)網(wǎng)頁(yè)http://10.3.1.254，選WEB Local，可以看到一臺(tái)顯示：
"test page on real server 1"，另一臺(tái)為"test page on real server 2",同時(shí)在Router上
ipvsadm可以看到每個(gè)real server的聯(lián)接數(shù)
8.設(shè)置FTP服務(wù)
#vi /etc/vsftpd/vsftp.conf，在兩臺(tái)real server上分別加入以下幾行：
anon_root=/u01/ftproot
local_root=/u01/ftproot
setproctitle_enable=YES
#service vsftpd start
現(xiàn)在LVM+GFS+ISCSI+TOMCAT就設(shè)置好了，我們可以用Apache Jmeter來(lái)測(cè)試LVM的性能，兩臺(tái)機(jī)子上
分別運(yùn)行jmeter，都指向10.3.1.254/myjsp/testoracle.jsp，各200個(gè)threads同時(shí)運(yùn)行，在Router
上用ipvsadm可以監(jiān)控，Oracle Server的性能可要好，否則大量的http進(jìn)程會(huì)hang在real server
上，ipvsadm也會(huì)顯示有個(gè)real server失去了。測(cè)試時(shí)real server的CPU idle會(huì)降到70%，而Router
的CPU idle幾乎不動(dòng)。 |
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發(fā)表于 2005-07-15 09:56
發(fā)表于 2005-07-19 21:35
