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Question

我的服務器上有一個以下elasticsearch配置文件。

#!/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

echo "Statement before >>>>"
. /lib/lsb/init-functions
echo "Statement after >>>>>"

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

# 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 configuration directory
CONF_DIR=/etc/$NAME

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

# Path to the GC log file
#ES_GC_LOG_FILE=/var/log/elasticsearch/gc.log

# Elasticsearch PID file directory
PID_DIR="/var/run/elasticsearch"

# Elasticsearch Repo directory
REPO_DIR="/mnt/backups"

# End of variables that can be overwritten in $DEFAULT

# overwrite settings from default file
if [ -f "$DEFAULT" ]; then
    . "$DEFAULT"
fi
# CONF_FILE setting was removed
if [ ! -z "$CONF_FILE" ]; then
    echo "CONF_FILE setting is no longer supported. elasticsearch.yml must be placed in the config directory and cannot be renamed."
    exit 1
fi

# Define other required variables
PID_FILE="$PID_DIR/$NAME.pid"
DAEMON=$ES_HOME/bin/elasticsearch
DAEMON_OPTS="-d -p $PID_FILE --default.path.home=$ES_HOME --default.path.logs=$LOG_DIR --default.path.data=$DATA_DIR --default.path.conf=$CONF_DIR --default.path.repo=$REPO_DIR"
export ES_HEAP_SIZE
export ES_HEAP_NEWSIZE
export ES_DIRECT_SIZE
export ES_JAVA_OPTS
export ES_GC_LOG_FILE
export JAVA_HOME

# 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.1"
        log_end_msg 0
        exit 0
    fi

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

    # Ensure that the PID_DIR exists (it is cleaned at OS startup time)
    if [ -n "$PID_DIR" ] && [ ! -e "$PID_DIR" ]; then
        mkdir -p "$PID_DIR" && chown "$ES_USER":"$ES_GROUP" "$PID_DIR"
    fi
    if [ -n "$PID_FILE" ] && [ ! -e "$PID_FILE" ]; then
        touch "$PID_FILE" && chown "$ES_USER":"$ES_GROUP" "$PID_FILE"
    fi

    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
        echo "Staring......."
        echo $DAEMON_OPTS
    # Start Daemon
    start-stop-daemon -d $ES_HOME --start -b --user "$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))
            if [ $i -gt $timeout ]; then
                log_end_msg 1
                exit 1
            fi
        done
    fi
    log_end_msg $return
    exit $return
    ;;
  stop)
    log_daemon_msg "Stopping $DESC"

    if [ -f "$PID_FILE" ]; then
        start-stop-daemon --stop --pidfile "$PID_FILE" \
            --user "$ES_USER" \
            --quiet \
            --retry forever/TERM/20 > /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

注意

echo "Statement before >>>>"
. /lib/lsb/init-functions
echo "Statement after >>>>>"

現在，每次運行上述腳本時，我都會看到Statement before >>>>的Statement before >>>>打印出來，而Statement after >>>>卻看不到

原因：我對DAEMON_OPTS變量所做的更改很少，但是每次我重新啟動DAEMON_OPTS時，都看不到應用選項（當我執行ps aux | grep elasticsearch ）

@rici：

Distributor ID: Debian
Description:    Debian GNU/Linux 8.3 (jessie)
Release:    8.3
Codename:   jessie

dpkg -S "$(ps -ocmd= 1)"
systemd-sysv: /sbin/init

Answer 1

您的服務器正在使用systemd init系統 ，這意味着您可能無法僅編輯init.d腳本，並期望更改會反映在啟動過程中。

像新貴一樣，systemd修改/lib/lsb/init-functions 。 在SysV中，此文件只是有用的Shell函數的集合，幾乎所有初始化腳本都使用該函數。 因此，該文件包含在每個初始化腳本的開頭附近。 （Debian的linter軟件包實際上會檢查以確保是這種情況。）因此systemd（和upstart）可以將代碼插入此文件，從而運行替代服務控制命令。 對於systemd init-functions ，該文件調用systemd servicectl ，該servicectl使用systemd配置文件進行服務，然后退出。 （Upstart exec的服務控制器具有相同的最終效果。）

systemd中還有一個“生成器”，它試圖為所有舊版init.d服務創建systemd配置文件[注1]，但是在elasticsearch的情況下，這可能無關緊要，因為elasticsearch似乎是與systemd配置文件一起提供的 。

因此，為了更改您的elasticsearch啟動配置，您將必須修改systemd服務條目 。

似乎相對清楚的是，您在問題中顯示的init腳本不是為啟動服務而實際運行的腳本。 比較腳本中的日志記錄行：

DESC="Elasticsearch Server"
#...
log_daemon_msg "Starting $DESC"

實際觀察到的輸出：

[Ok] Starting elasticsearch (via systemctl): elasticsearch.service.

無論log_daemon_msg做什么，都不太可能將Elasticsearch Server更改為elasticsearch ，並且實際產生的輸出行顯然來自systemd。

---

筆記

1. 該頁面對systemd遺留系統進行了有趣的討論-“ systemd sysv init兼容模式很神奇”-盡管第一個評論（來自John Carver）也很有趣。 但是我認為這與您的問題無關。

Answer 2

請務必閱讀@rici答案以獲取解釋。 以下答案僅包含一些附加信息。

因此，正如@rici指出的那樣。

Like upstart, systemd modifies /lib/lsb/init-functions

如果您仔細檢查/lib/lsb/init-functions

最后幾行如下所示。

for hook in $(run-parts --lsbsysinit --list /lib/lsb/init-functions.d 2>/dev/null); do
    [ -r $hook ] && . $hook || true
done

在這里/lib/lsb/init-functions.d/40-systemd的調用（或調用）

此外，必須要讀this也