如何保持弹性搜索在 Linux 服务器上运行

Question

我正在通过 Putty 客户端使用 ssh 访问我的服务器，但是当我的 putty 处于非活动状态或我关闭它时，弹性搜索停止。我想让它一直运行。我怎样才能做到这一点？

Answer 1

您遇到的问题是 elasticsearch 没有作为守护程序（服务器）启动。相反，您可以像启动普通程序一样启动它。因此，当您停止 SSH 会话时，程序将停止运行。

为了让elasticsearch在服务器本身重启时启动，你需要在服务器启动时添加elasticsearch。

您没有说明您在服务器上运行的操作系统。假设它是一个 Debian（例如 Ubuntu）系统），您必须创建一个可以放在目录 /etc/init.d 中的文件。

我已经从下面我自己的服务器复制了文件。您可能已经拥有它。 查找文件 /etc/init.d/elasticsearch

$ more /etc/init.d/elasticsearch 

获得文件后，您可以运行命令

sudo update-rc.d elasticsearch defaults 95 10

这会将elasticsearch“安装”为服务。

要启动和停止服务，您可以运行以下命令：

sudo  service elasticsearch start
sudo  service elasticsearch stop

如果您还没有该文件，请在下面。

#!/bin/sh
#
# /etc/init.d/elasticsearch -- startup script for Elasticsearch
#
# Written by Miquel van Smoorenburg <miquels@cistron.nl>.
# Modified for Debian GNU/Linux by Ian Murdock <imurdock@gnu.ai.mit.edu>.
# Modified for Tomcat by Stefan Gybas <sgybas@debian.org>.
# Modified for Tomcat6 by Thierry Carrez <thierry.carrez@ubuntu.com>.
# Additional improvements by Jason Brittain <jason.brittain@mulesoft.com>.
# Modified by Nicolas Huray for Elasticsearch <nicolas.huray@gmail.com>.
#
### BEGIN INIT INFO
# Provides:          elasticsearch
# Required-Start:    $network $remote_fs $named
# Required-Stop:     $network $remote_fs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Starts elasticsearch
# Description:       Starts elasticsearch using start-stop-daemon
### END INIT INFO

PATH=/bin:/usr/bin:/sbin:/usr/sbin
NAME=elasticsearch
DESC="Elasticsearch Server"
DEFAULT=/etc/default/$NAME

if [ `id -u` -ne 0 ]; then
    echo "You need root privileges to run this script"
    exit 1
fi


. /lib/lsb/init-functions

if [ -r /etc/default/rcS ]; then
    . /etc/default/rcS
fi


# The following variables can be overwritten in $DEFAULT

# Run Elasticsearch as this user ID and group ID
ES_USER=elasticsearch
ES_GROUP=elasticsearch

# The first existing directory is used for JAVA_HOME (if JAVA_HOME is not defined in $DEFAULT)
JDK_DIRS="/usr/lib/jvm/java-8-oracle/ /usr/lib/jvm/j2sdk1.8-oracle/ /usr/lib/jvm/jdk-7-oracle-x64 /usr/lib/jvm/java-7-oracle /usr/lib/jvm/j2sdk1.7-oracle/ /usr/lib/jvm/jav
a-7-openjdk /usr/lib/jvm/java-7-openjdk-amd64/ /usr/lib/jvm/java-7-openjdk-armhf /usr/lib/jvm/java-7-openjdk-i386/ /usr/lib/jvm/default-java"

# Look for the right JVM to use
for jdir in $JDK_DIRS; do
    if [ -r "$jdir/bin/java" -a -z "${JAVA_HOME}" ]; then
        JAVA_HOME="$jdir"
    fi
done
export JAVA_HOME

# Directory where the Elasticsearch binary distribution resides
ES_HOME=/usr/share/$NAME

# Heap size defaults to 256m min, 1g max
# Set ES_HEAP_SIZE to 50% of available RAM, but no more than 31g
#ES_HEAP_SIZE=2g

# Heap new generation
#ES_HEAP_NEWSIZE=

# max direct memory
#ES_DIRECT_SIZE=

# Additional Java OPTS
#ES_JAVA_OPTS=

# Maximum number of open files
MAX_OPEN_FILES=65535

# Maximum amount of locked memory
#MAX_LOCKED_MEMORY=

# Elasticsearch log directory
LOG_DIR=/var/log/$NAME

# Elasticsearch data directory
DATA_DIR=/var/lib/$NAME

# Elasticsearch work directory
WORK_DIR=/tmp/$NAME

# Elasticsearch configuration directory
CONF_DIR=/etc/$NAME

# Elasticsearch configuration file (elasticsearch.yml)
CONF_FILE=$CONF_DIR/elasticsearch.yml

# Maximum number of VMA (Virtual Memory Areas) a process can own
MAX_MAP_COUNT=262144

# End of variables that can be overwritten in $DEFAULT

# overwrite settings from default file
if [ -f "$DEFAULT" ]; then
    . "$DEFAULT"
fi

# Define other required variables
PID_FILE=/var/run/$NAME.pid
DAEMON=$ES_HOME/bin/elasticsearch
DAEMON_OPTS="-d -p $PID_FILE --default.config=$CONF_FILE --default.path.home=$ES_HOME --default.path.logs=$LOG_DIR --default.path.data=$DATA_DIR --default.path.work=$WORK_
DIR --default.path.conf=$CONF_DIR"

export ES_HEAP_SIZE
export ES_HEAP_NEWSIZE
export ES_DIRECT_SIZE
export ES_JAVA_OPTS

# Check DAEMON exists
test -x $DAEMON || exit 0

checkJava() {
    if [ -x "$JAVA_HOME/bin/java" ]; then
        JAVA="$JAVA_HOME/bin/java"
    else
        JAVA=`which java`
    fi

    if [ ! -x "$JAVA" ]; then
        echo "Could not find any executable java binary. Please install java in your PATH or set JAVA_HOME"
        exit 1
    fi
}

case "$1" in
  start)
    checkJava

    if [ -n "$MAX_LOCKED_MEMORY" -a -z "$ES_HEAP_SIZE" ]; then
        log_failure_msg "MAX_LOCKED_MEMORY is set - ES_HEAP_SIZE must also be set"
        exit 1
    fi

    log_daemon_msg "Starting $DESC"

    pid=`pidofproc -p $PID_FILE elasticsearch`
    if [ -n "$pid" ] ; then
        log_begin_msg "Already running."
        log_end_msg 0
        exit 0
    fi

    # Prepare environment
    mkdir -p "$LOG_DIR" "$DATA_DIR" "$WORK_DIR" && chown "$ES_USER":"$ES_GROUP" "$LOG_DIR" "$DATA_DIR" "$WORK_DIR"
    touch "$PID_FILE" && chown "$ES_USER":"$ES_GROUP" "$PID_FILE"

    if [ -n "$MAX_OPEN_FILES" ]; then
        ulimit -n $MAX_OPEN_FILES
    fi

    if [ -n "$MAX_LOCKED_MEMORY" ]; then
        ulimit -l $MAX_LOCKED_MEMORY
    fi

    if [ -n "$MAX_MAP_COUNT" -a -f /proc/sys/vm/max_map_count ]; then
        sysctl -q -w vm.max_map_count=$MAX_MAP_COUNT
    fi

    # Start Daemon
    start-stop-daemon --start -b --user "$ES_USER" -c "$ES_USER" --pidfile "$PID_FILE" --exec $DAEMON -- $DAEMON_OPTS
    return=$?
    if [ $return -eq 0 ]
    then
        i=0
        timeout=10
        # Wait for the process to be properly started before exiting
        until { cat "$PID_FILE" | xargs kill -0; } >/dev/null 2>&1
        do
            sleep 1
            i=$(($i + 1))
            [ $i -gt $timeout ] && log_end_msg 1
        done
    else
        log_end_msg $return
    fi
    ;;      
  stop)
    log_daemon_msg "Stopping $DESC"

    if [ -f "$PID_FILE" ]; then 
        start-stop-daemon --stop --pidfile "$PID_FILE" \
            --user "$ES_USER" \
            --retry=TERM/20/KILL/5 >/dev/null
        if [ $? -eq 1 ]; then
            log_progress_msg "$DESC is not running but pid file exists, cleaning up"
        elif [ $? -eq 3 ]; then
            PID="`cat $PID_FILE`"
            log_failure_msg "Failed to stop $DESC (pid $PID)"
            exit 1
        fi
        rm -f "$PID_FILE"
    else
        log_progress_msg "(not running)"
    fi
    log_end_msg 0
    ;;
  status)
    status_of_proc -p $PID_FILE elasticsearch elasticsearch && exit 0 || exit $?
    ;;
  restart|force-reload)
    if [ -f "$PID_FILE" ]; then
        $0 stop
        sleep 1
    fi
    $0 start
    ;;
  *)
    log_success_msg "Usage: $0 {start|stop|restart|force-reload|status}"
    exit 1
    ;;
esac

exit 0

Answer 2

我需要使用 debian 包安装 ElasticSearch。详情看这里https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-elasticsearch-on-ubuntu-14-04

Answer 3

如果你没有 sudo 访问权限，可以使用nohup 确保它在连接断开后继续运行。

只需运行nohup [start elasticsearch command] > es.out &。输出将附加到 es.out，您可以在文本编辑器中阅读，或使用tail -f nohup.out 作为提要获取。 希望这会有所帮助。

Answer 4

以下对我有用：( elasticsearch-7.8.0 )

1. 导航到elasticsearch-7.8.0/bin目录
2. 运行nohup ./elasticsearch &
3. 它将在后台启动弹性搜索，并将日志附加到同一目录下的 nohup.out 文件中。