最近我们在使用Jenkins自动化部署项目时,在生产liunx环境下,使用脚本shutdown.sh停止tomcat服务,然后再start之后发现应用无法访问了,后台查看tomcat进程是发现有个2个tomcat进程,说明之前的shutdown并没有完全停掉tomcat进程。那怎么样tomcat使用shutdown之后立马关掉其进程呢? 经查资料发现在shutdown.sh脚本之后有条命令是这样的:

exec "$PRGDIR"/"$EXECUTABLE" stop "$@"这个就是停止tomcat 服务的命令,我们只需要加一个  -force  就可以在shutdown时强制关闭tomcat进程

exec "$PRGDIR"/"$EXECUTABLE" stop -force "$@"

但光这样还是不行,再shutdown时报错:

Kill failed: $CATALINA_PID not set查找失败原因:

+ FORCE=1

+ '[' '!' -z '' ']'

+ /usr/java/jdk1.6.0_38/bin/java -server -Xms2048m -Xmx2048m -Xmn768m -XX:PermSize=128m -XX:MaxPermSize=256m -XX:+UseParallelOldGC -XX:+PrintGCDateStamps -XX:+PrintGCDetails -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/home/xrltest1/tomcat/dumpfile/heap.bin -Xloggc:/home/xrltest1/tomcat/logs/gc.log -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/home/xrltest1/tomcat/endorsed -classpath /home/xrltest1/tomcat/bin/bootstrap.jar -Dcatalina.base=/home/xrltest1/tomcat -Dcatalina.home=/home/xrltest1/tomcat -Djava.io.tmpdir=/home/xrltest1/tomcat/temp org.apache.catalina.startup.Bootstrap stop

2015-3-21 11:59:53 org.apache.catalina.startup.Catalina stopServer

严重: Catalina.stop:

java.net.ConnectException: Connection refused

at java.net.PlainSocketImpl.socketConnect(Native Method)

at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)

at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)

at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)

at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)

at java.net.Socket.connect(Socket.java:529)

at java.net.Socket.connect(Socket.java:478)

at java.net.Socket.(Socket.java:375)

at java.net.Socket.(Socket.java:189)

at org.apache.catalina.startup.Catalina.stopServer(Catalina.java:422)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at org.apache.catalina.startup.Bootstrap.stopServer(Bootstrap.java:338)

at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:416)

+ '[' '!' -z '' ']'

+ '[' 1 -eq 1 ']'

+ '[' -z '' ']'

+ echo 'Kill failed: $CATALINA_PID not set'

Kill failed: $CATALINA_PID not set

从中可以看到,首先是执行java命令失败,没有停止tomcat,然后执行-force模块的命令,但是却没有找到$CATALINA_PID设定的进程号,我们先不去关注java执行stop命令为什么报错,而是看看为什么加了-force参数也不起作用了

为什么没有$CATALINA_PID?接下来就带大家一探究竟

首先,我们将涉及到$CATALINA_PID变量的代码全部提取出来:

第一处:

#以下这句判断设置的$CATALINA_PID变量如果不存在,则显示"Using CATALINA_PID:

$CATALINA_PID",如果存在则不显示

if [ ! -z "$CATALINA_PID" ]; then

echo "Using CATALINA_PID:    $CATALINA_PID"

fi

fi#貌似只是判断$CATALINA_PID是否是空字符,其他什么都没有做

第二处:(涉及到start参数的模块内的$CATALINA_PID变量,只是提出来分析,其实不对stop模块有影响)

#这个是start模块内的代码

"$_RUNJAVA" "$LOGGING_CONFIG" $JAVA_OPTS $CATALINA_OPTS \

-Djava.endorsed.dirs="$JAVA_ENDORSED_DIRS" -classpath "$CLASSPATH" \

-Dcatalina.base="$CATALINA_BASE" \

-Dcatalina.home="$CATALINA_HOME" \

-Djava.io.tmpdir="$CATALINA_TMPDIR" \

org.apache.catalina.startup.Bootstrap "$@" start \

>> "$CATALINA_OUT" 2>&1 &

#从&可以看出启动的命令在后台启动

fi

if [ ! -z "$CATALINA_PID" ]; then

#判断CATALINA_PID如果不是空字符,则将Shell最后运行的后台Process的PID 传给$CATALINA_PID

echo $! > "$CATALINA_PID"

#在使用命令运行进程至后台时,可以使用$!抓取前面启动运行在后台进程的进程号

fi

fi

#上面语句是tomcat在启动时,会将$CATALINA_PID写入PID进程号第三处:

#一下语句都出现在stop模块内

if [ ! -z "$CATALINA_PID" ]; then

#$CATALINA_PID文件不是非空

if [ -f "$CATALINA_PID" ]; then

if [ -s "$CATALINA_PID" ]; then

kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1

#kill -0 pid 不发送任何信号,但是系统会进行错误检查。

if [ $? -gt 0 ]; then

echo "PID file found but no matching process was found. Stop aborted."

exit 1

fi

else

echo "PID file is empty and has been ignored."

fi

else

echo "\$CATALINA_PID was set but the specified file does not exist. Is Tomcat running? Stop aborted."

exit 1

fi

fi

#如果发现$CATALINA_PID则发送一个模拟结束进程的型号,如果返回值为0,则正常,其他则异常,做退出操作

#从上面的sh -x输出的信息对应的是:'[' '!' -z '' ']' 可以看出$CATALINA_PID变量没有设定,所以这个判断直接就结束了,什么都没做

第四处:

#下面的代码紧接着stop的正常停止代码下

if [ ! -z "$CATALINA_PID" ]; then

#如果$CATALINA_PID不为空

if [ -f "$CATALINA_PID" ]; then

#而且还是普通文件

while [ $SLEEP -ge 0 ]; do

#而且$SLEEP还大于0

kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1

#则测试下tomcat能不能被关闭

if [ $? -gt 0 ]; then

#剩下的参数还有,则清空$CATALINA_PID

rm -f "$CATALINA_PID" >/dev/null 2>&1

if [ $? != 0 ]; then

if [ -w "$CATALINA_PID" ]; then

cat /dev/null > "$CATALINA_PID"

else

echo "Tomcat stopped but the PID file could not be removed or cleared."

fi

fi

break

fi

if [ $SLEEP -gt 0 ]; then

sleep 1

fi

if [ $SLEEP -eq 0 ]; then

if [ $FORCE -eq 0 ]; then

echo "Tomcat did not stop in time. PID file was not removed."

fi

fi

SLEEP=`expr $SLEEP - 1 `

done

fi

fi

#上段语句主要是判断tomcat是否被关闭

#核心语句还是:kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1

#while语句做sleep使用,用于清空$CATALINA_PID

#但是[ ! -z "$CATALINA_PID" ]导致这段语句什么都没做啊!!!!!第五处:

#这段代码就是涉及-force的核心代码了

if [ $FORCE -eq 1 ]; then

if [ -z "$CATALINA_PID" ]; then

echo "Kill failed: \$CATALINA_PID not set"

else

if [ -f "$CATALINA_PID" ]; then

PID=`cat "$CATALINA_PID"`

echo "Killing Tomcat with the PID: $PID"

kill -9 $PID

#强制执行的核心命令

rm -f "$CATALINA_PID" >/dev/null 2>&1

if [ $? != 0 ]; then

echo "Tomcat was killed but the PID file could not be removed."

fi

fi

fi

fi

#从中就可以看出,sh -x输出的Kill failed: $CATALINA_PID not set是怎么来的总结下,$CATALINA_PID在整个代码中的作用:

1.在tomcat启动时会写入$CATALINA_PID,但是假设我们的环境是多tomcat项目或$CATALINA_PID为空

2.stop代码中,检查$CATALINA_PID是否为空字符,是的话什么都不做

3.sstop代码中,检查$CATALINA_PID是否为空字符,是的话什么都不做

4.force代码中,检查$CATALINA_PID是否为空字符,是的话就报错

也就是说只要没有保存中这个项目的PID,那么正常stop停止不了,-force也是没有用的。

那么该如何解决呢?直接给$CATALINA_PID付PID的值,那么看结果:

+ FORCE=1

+ '[' '!' -z 12031 ']'

+ '[' -f 12031 ']'

+ echo '$CATALINA_PID was set but the specified file does not exist. Is Tomcat running? Stop aborted.'

$CATALINA_PID was set but the specified file does not exist. Is Tomcat running? Stop aborted.涉及到的代码:

if [ -f "$CATALINA_PID" ]; then

if [ -s "$CATALINA_PID" ]; then

kill -0 `cat "$CATALINA_PID"` >/dev/null 2>&1

#kill -0 pid 不发送任何信号,但是系统会进行错误检查。

if [ $? -gt 0 ]; then

echo "PID file found but no matching process was found. Stop aborted."

exit 1

fi

else

echo "PID file is empty and has been ignored."

fi

else

echo "\$CATALINA_PID was set but the specified file does not exist. Is Tomcat running? Stop aborted."

exit 1

#$CATALINA_PID不是个文件,所以不好意思,我退出了....原来$CATALINA_PID还必须是个文件,那么我们可不可以建这么一个文件呢?

在catalina.sh脚本的代码前,加入以下语句:

#########################################################################################

if [ -z "$CATALINA_PID" ]; then

CATALINA_PID=$PRGDIR/CATALINA_PID

cat $CATALINA_PID

fi######################################################################################结果:tomcat停止执行成功,完成结束进程任务

总结:

在我看到的很到部署tomcat的文章中,还没发现有关于设置$CATALINA_PID��件路径的提示(也许是我看到的少),但是此处我要建议小伙伴们,在写tomcat启动、停止、重启的脚本的时候,一定要注意这个变量。

更多Tomcat相关教程见以下内容:

Tomcat 的详细介绍:请点这里

Tomcat 的下载地址:请点这里

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