wget http://mirrors.hust.edu.cn/apache/zookeeper/stable/zookeeper-3.4.6.tar.gz
cp zookeeper-3.4.6.tar.gz /usr/local
cd /usr/local
tar zxvf zookeeper-3.4.6.tar.gz
ln -s /usr/local/zookeeper-3.4.6 /usr/local/zookeeper

ls -al /usr/local/zookeeper/bin

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

README.txt

zkCleanup.sh

zkCli.cmd

zkCli.sh

zkEnv.cmd

zkEnv.sh

zkServer.cmd

zkServer.sh

/usr/local/zookeeper/bin/zkServer.sh start 

.......

ZOOBIN="${BASH_SOURCE-$0}"

ZOOBIN="$(dirname "${ZOOBIN}")"

ZOOBINDIR="$(cd "${ZOOBIN}"; pwd)"         //获得当前脚本文件所在路径  本例中 ZOOBINDIR 的值为 /usr/local/zookeeper/bin

if [ -e "$ZOOBIN/../libexec/zkEnv.sh" ]; then

  . "$ZOOBINDIR/../libexec/zkEnv.sh"

else

  . "$ZOOBINDIR/zkEnv.sh"                  //执行环境配置脚本

fi

ZOOBINDIR="${ZOOBINDIR:-/usr/bin}"                //如果ZOOBINDIR 为空的话 那么默认指为 /usr/bin

ZOOKEEPER_PREFIX="${ZOOBINDIR}/.."                

if [ "x$ZOOCFGDIR" = "x" ]

then

  if [ -e "${ZOOKEEPER_PREFIX}/conf" ]; then      //如果前面 ZOOKEEPER_PREFIX/conf 存在

    ZOOCFGDIR="$ZOOBINDIR/../conf"                //那么配置文件目录 就为该值 在本例中 为 /usr/local/zookeeper/conf

  else

    ZOOCFGDIR="$ZOOBINDIR/../etc/zookeeper"

  fi

fi

if [ -f "${ZOOCFGDIR}/zookeeper-env.sh" ]; then

  . "${ZOOCFGDIR}/zookeeper-env.sh"

fi

if [ "x$ZOOCFG" = "x" ]

then

    ZOOCFG="zoo.cfg"                              //配置文件默认名称  zoo.cfg

fi

ZOOCFG="$ZOOCFGDIR/$ZOOCFG"                       //完整配置路径   /usr/local/zookeeper/conf/zoo.cfg

......
//后面代码主要是用来声明 classpath

.......

//看这段代码

if [ "x$2" != "x" ]                  //如果启动文件 输入了第2个参数 那么配置文件使用指定的文件名

then

    ZOOCFG="$ZOOCFGDIR/$2"

fi

# if we give a more complicated path to the config, don't screw around in $ZOOCFGDIR

if [ "x$(dirname "$ZOOCFG")" != "x$ZOOCFGDIR" ]

then

    ZOOCFG="$2"

fi

if [ -z "$ZOOPIDFILE" ]; then

    ZOO_DATADIR="$(grep "^[[:space:]]*dataDir" "$ZOOCFG" | sed -e 's/.*=//')"

    if [ ! -d "$ZOO_DATADIR" ]; then

        mkdir -p "$ZOO_DATADIR"

    fi

    ZOOPIDFILE="$ZOO_DATADIR/zookeeper_server.pid"

else

    # ensure it exists, otw stop will fail

    mkdir -p "$(dirname "$ZOOPIDFILE")"

fi

cd /usr/local/zookeeper/conf/

cp zoo_sample.cfg zoo.cfg                 //zoo.cfg 就是启动需要读取的配置文件

mkdir -p /usr/local/zookeeper/data

# The number of milliseconds of each tick

tickTime=2000

# The number of ticks that the initial

# synchronization phase can take

initLimit=

# The number of ticks that can pass between

# sending a request and getting an acknowledgement

syncLimit=

# the directory where the snapshot is stored.

# do not use /tmp for storage, /tmp here is just

# example sakes.

dataDir=/usr/local/zookeeper/data

# the port at which the clients will connect

clientPort=

/usr/local/zookeeper/bin/zkServer.sh start

/usr/local/zookeeper/bin/zkCli.sh -server 127.0.0.1