Celery Daemon "cannot connect to amqp"

0
votes

I'm trying to run celery as a daemon in the background on Ubuntu 14.04.

I've followed the instructions at http://celery.readthedocs.org/en/latest/tutorials/daemonizing.html and used the celeryd shell script

#!/bin/sh -e
# ============================================
#  celeryd - Starts the Celery worker daemon.
# ============================================
#
# :Usage: /etc/init.d/celeryd {start|stop|force-reload|restart|try-restart|status}
# :Configuration file: /etc/default/celeryd
#
# See http://docs.celeryproject.org/en/latest/tutorials/daemonizing.html#generic-init-scripts


### BEGIN INIT INFO
# Provides:          celeryd
# Required-Start:    $network $local_fs $remote_fs
# Required-Stop:     $network $local_fs $remote_fs
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: celery task worker daemon
### END INIT INFO
#
#
# To implement separate init scripts, copy this script and give it a different
# name:
# I.e., if my new application, "little-worker" needs an init, I
# should just use:
#
#   cp /etc/init.d/celeryd /etc/init.d/little-worker
#
# You can then configure this by manipulating /etc/default/little-worker.
#
VERSION=10.1
echo "celery init v${VERSION}."
if [ $(id -u) -ne 0 ]; then
    echo "Error: This program can only be used by the root user."
    echo "       Unprivileged users must use the 'celery multi' utility, "
    echo "       or 'celery worker --detach'."
    exit 1
fi


# Can be a runlevel symlink (e.g. S02celeryd)
if [ -L "$0" ]; then
    SCRIPT_FILE=$(readlink "$0")
else
    SCRIPT_FILE="$0"
fi
SCRIPT_NAME="$(basename "$SCRIPT_FILE")"

DEFAULT_USER="celery"
DEFAULT_PID_FILE="/var/run/celery/%n.pid"
DEFAULT_LOG_FILE="/var/log/celery/%n.log"
DEFAULT_LOG_LEVEL="INFO"
DEFAULT_NODES="celery"
DEFAULT_CELERYD="-m celery worker --detach"

CELERY_DEFAULTS=${CELERY_DEFAULTS:-"/etc/default/${SCRIPT_NAME}"}

# Make sure executable configuration script is owned by root
_config_sanity() {
    local path="$1"
    local owner=$(ls -ld "$path" | awk '{print $3}')
    local iwgrp=$(ls -ld "$path" | cut -b 6)
    local iwoth=$(ls -ld "$path" | cut -b 9)

    if [ "$(id -u $owner)" != "0" ]; then
        echo "Error: Config script '$path' must be owned by root!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with mailicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change ownership of the script:"
        echo "    $ sudo chown root '$path'"
        exit 1
    fi

    if [ "$iwoth" != "-" ]; then  # S_IWOTH
        echo "Error: Config script '$path' cannot be writable by others!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with malicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change the scripts permissions:"
        echo "    $ sudo chmod 640 '$path'"
        exit 1
    fi
    if [ "$iwgrp" != "-" ]; then  # S_IWGRP
        echo "Error: Config script '$path' cannot be writable by group!"
        echo
        echo "Resolution:"
        echo "Review the file carefully and make sure it has not been "
        echo "modified with malicious intent.  When sure the "
        echo "script is safe to execute with superuser privileges "
        echo "you can change the scripts permissions:"
        echo "    $ sudo chmod 640 '$path'"
        exit 1
    fi
}

if [ -f "$CELERY_DEFAULTS" ]; then
    _config_sanity "$CELERY_DEFAULTS"
    echo "Using config script: $CELERY_DEFAULTS"
    . "$CELERY_DEFAULTS"
fi

# Sets --app argument for CELERY_BIN
CELERY_APP_ARG=""
if [ ! -z "$CELERY_APP" ]; then
    CELERY_APP_ARG="--app=$CELERY_APP"
fi

CELERYD_USER=${CELERYD_USER:-$DEFAULT_USER}

# Set CELERY_CREATE_DIRS to always create log/pid dirs.
CELERY_CREATE_DIRS=${CELERY_CREATE_DIRS:-0}
CELERY_CREATE_RUNDIR=$CELERY_CREATE_DIRS
CELERY_CREATE_LOGDIR=$CELERY_CREATE_DIRS
if [ -z "$CELERYD_PID_FILE" ]; then
    CELERYD_PID_FILE="$DEFAULT_PID_FILE"
    CELERY_CREATE_RUNDIR=1
fi
if [ -z "$CELERYD_LOG_FILE" ]; then
    CELERYD_LOG_FILE="$DEFAULT_LOG_FILE"
    CELERY_CREATE_LOGDIR=1
fi

CELERYD_LOG_LEVEL=${CELERYD_LOG_LEVEL:-${CELERYD_LOGLEVEL:-$DEFAULT_LOG_LEVEL}}
CELERY_BIN=${CELERY_BIN:-"celery"}
CELERYD_MULTI=${CELERYD_MULTI:-"$CELERY_BIN multi"}
CELERYD_NODES=${CELERYD_NODES:-$DEFAULT_NODES}

export CELERY_LOADER

if [ -n "$2" ]; then
    CELERYD_OPTS="$CELERYD_OPTS $2"
fi

CELERYD_LOG_DIR=`dirname $CELERYD_LOG_FILE`
CELERYD_PID_DIR=`dirname $CELERYD_PID_FILE`

# Extra start-stop-daemon options, like user/group.
if [ -n "$CELERYD_CHDIR" ]; then
    DAEMON_OPTS="$DAEMON_OPTS --workdir=$CELERYD_CHDIR"
fi


check_dev_null() {
    if [ ! -c /dev/null ]; then
        echo "/dev/null is not a character device!"
        exit 75  # EX_TEMPFAIL
    fi
}


maybe_die() {
    if [ $? -ne 0 ]; then
        echo "Exiting: $* (errno $?)"
        exit 77  # EX_NOPERM
    fi
}

create_default_dir() {
    if [ ! -d "$1" ]; then
        echo "- Creating default directory: '$1'"
        mkdir -p "$1"
        maybe_die "Couldn't create directory $1"
        echo "- Changing permissions of '$1' to 02755"
        chmod 02755 "$1"
        maybe_die "Couldn't change permissions for $1"
        if [ -n "$CELERYD_USER" ]; then
            echo "- Changing owner of '$1' to '$CELERYD_USER'"
            chown "$CELERYD_USER" "$1"
            maybe_die "Couldn't change owner of $1"
        fi
        if [ -n "$CELERYD_GROUP" ]; then
            echo "- Changing group of '$1' to '$CELERYD_GROUP'"
            chgrp "$CELERYD_GROUP" "$1"
            maybe_die "Couldn't change group of $1"
        fi
    fi
}


check_paths() {
    if [ $CELERY_CREATE_LOGDIR -eq 1 ]; then
        create_default_dir "$CELERYD_LOG_DIR"
    fi
    if [ $CELERY_CREATE_RUNDIR -eq 1 ]; then
        create_default_dir "$CELERYD_PID_DIR"
    fi
}

create_paths() {
    create_default_dir "$CELERYD_LOG_DIR"
    create_default_dir "$CELERYD_PID_DIR"
}

export PATH="${PATH:+$PATH:}/usr/sbin:/sbin"


_get_pidfiles () {
    # note: multi < 3.1.14 output to stderr, not stdout, hence the redirect.
    ${CELERYD_MULTI} expand "${CELERYD_PID_FILE}" ${CELERYD_NODES} 2>&1
}


_get_pids() {
    found_pids=0
    my_exitcode=0

    for pidfile in $(_get_pidfiles); do
        local pid=`cat "$pidfile"`
        local cleaned_pid=`echo "$pid" | sed -e 's/[^0-9]//g'`
        if [ -z "$pid" ] || [ "$cleaned_pid" != "$pid" ]; then
            echo "bad pid file ($pidfile)"
            one_failed=true
            my_exitcode=1
        else
            found_pids=1
            echo "$pid"
        fi

    if [ $found_pids -eq 0 ]; then
        echo "${SCRIPT_NAME}: All nodes down"
        exit $my_exitcode
    fi
    done
}


_chuid () {
    su "$CELERYD_USER" -c "$CELERYD_MULTI $*"
}


start_workers () {
    if [ ! -z "$CELERYD_ULIMIT" ]; then
        ulimit $CELERYD_ULIMIT
    fi
    _chuid $* start $CELERYD_NODES $DAEMON_OPTS     \
                 --pidfile="$CELERYD_PID_FILE"      \
                 --logfile="$CELERYD_LOG_FILE"      \
                 --loglevel="$CELERYD_LOG_LEVEL"    \
                 $CELERY_APP_ARG                    \
                 $CELERYD_OPTS
}


dryrun () {
    (C_FAKEFORK=1 start_workers --verbose)
}


stop_workers () {
    _chuid stopwait $CELERYD_NODES --pidfile="$CELERYD_PID_FILE"
}


restart_workers () {
    _chuid restart $CELERYD_NODES $DAEMON_OPTS      \
                   --pidfile="$CELERYD_PID_FILE"    \
                   --logfile="$CELERYD_LOG_FILE"    \
                   --loglevel="$CELERYD_LOG_LEVEL"  \
                   $CELERY_APP_ARG                  \
                   $CELERYD_OPTS
}


kill_workers() {
    _chuid kill $CELERYD_NODES --pidfile="$CELERYD_PID_FILE"
}


restart_workers_graceful () {
    echo "WARNING: Use with caution in production"
    echo "The workers will attempt to restart, but they may not be able to."
    local worker_pids=
    worker_pids=`_get_pids`
    [ "$one_failed" ] && exit 1

    for worker_pid in $worker_pids; do
        local failed=
        kill -HUP $worker_pid 2> /dev/null || failed=true
        if [ "$failed" ]; then
            echo "${SCRIPT_NAME} worker (pid $worker_pid) could not be restarted"
            one_failed=true
        else
            echo "${SCRIPT_NAME} worker (pid $worker_pid) received SIGHUP"
        fi
    done

    [ "$one_failed" ] && exit 1 || exit 0
}


check_status () {
    my_exitcode=0
    found_pids=0

    local one_failed=
    for pidfile in $(_get_pidfiles); do
        if [ ! -r $pidfile ]; then
            echo "${SCRIPT_NAME} down: no pidfiles found"
            one_failed=true
            break
        fi

        local node=`basename "$pidfile" .pid`
        local pid=`cat "$pidfile"`
        local cleaned_pid=`echo "$pid" | sed -e 's/[^0-9]//g'`
        if [ -z "$pid" ] || [ "$cleaned_pid" != "$pid" ]; then
            echo "bad pid file ($pidfile)"
            one_failed=true
        else
            local failed=
            kill -0 $pid 2> /dev/null || failed=true
            if [ "$failed" ]; then
                echo "${SCRIPT_NAME} (node $node) (pid $pid) is down, but pidfile exists!"
                one_failed=true
            else
                echo "${SCRIPT_NAME} (node $node) (pid $pid) is up..."
            fi
        fi
    done

    [ "$one_failed" ] && exit 1 || exit 0
}


case "$1" in
    start)
        check_dev_null
        check_paths
        start_workers
    ;;

    stop)
        check_dev_null
        check_paths
        stop_workers
    ;;

    reload|force-reload)
        echo "Use restart"
    ;;

    status)
        check_status
    ;;

    restart)
        check_dev_null
        check_paths
        restart_workers
    ;;

    graceful)
        check_dev_null
        restart_workers_graceful
    ;;

    kill)
        check_dev_null
        kill_workers
    ;;

    dryrun)
        check_dev_null
        dryrun
    ;;

    try-restart)
        check_dev_null
        check_paths
        restart_workers
    ;;

    create-paths)
        check_dev_null
        create_paths
    ;;

    check-paths)
        check_dev_null
        check_paths
    ;;

    *)
        echo "Usage: /etc/init.d/${SCRIPT_NAME} {start|stop|restart|graceful|kill|dryrun|create-paths}"
        exit 64  # EX_USAGE
    ;;
esac

exit 0
,

which I put in /etc/init.d/celeryd.

I've also got the following config filw (also called celeryd which lives in etc/default/celeryd

# Names of nodes to start
#   most will only start one node:
CELERYD_NODES="worker"

#   but you can also start multiple and configure settings
#   for each in CELERYD_OPTS (see `celery multi --help` for examples).

# Absolute or relative path to the 'celery' command:
CELERY_BIN="/usr/local/bin/celery"

# App instance to use
# comment out this line if you don't use an app
CELERY_APP="proj"
# or fully qualified:
#CELERY_APP="proj.tasks:app"

# Where to chdir at start.
CELERYD_CHDIR="/home/drmclean/"

# Extra command-line arguments to the worker
CELERYD_OPTS="--time-limit=300 --concurrency=8"

# %N will be replaced with the first part of the nodename.
CELERYD_LOG_FILE="/var/log/celery/%N.log"
CELERYD_PID_FILE="/var/run/celery/%N.pid"

# Workers should run as an unprivileged user.
#   You need to create this user manually (or you can choose
#   a user/group combination that already exists, e.g. nobody).
CELERYD_USER="drmclean"
CELERYD_GROUP="drmclean"

# If enabled pid and log directories will be created if missing,
# and owned by the userid/group configured.
CELERY_CREATE_DIRS=1

I can easily start the celery service running by using the command:

sudo /etc/init.d/celeryd start

and the service runs as I expect.

However on start-up the service never runs. When I inspect the logfile for the celery, it says.

"[2014-09-17 16:27:41,541: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 111] Connection refused. Trying again in 2.00 seconds..."

Can anyone help with this error? I can't see when the connection would be refused on start-up but also when using the sudo /etc/init.d/celeryd start command?

2
connectionrabbitmqcelerydaemon
Have you check rabbitmq? 127.0.0.1:5672 - ant31
What does this question mean? Check what about Rabbitmq? check it when? How should I check it? - David McLean
Celery is trying to connect to the rabbitmq server located on your locahost listening on port 5672. Have you checked if this rabbitmq server is up? Otherwise celery can't start - ant31

2 Answers

0
votes

Are you connecting from a remote server? If yes, the guest user is not allowed to connect from a remote server. See https://www.rabbitmq.com/access-control.html

0
votes

No the entire thing is running on my own machine. Actually it appears that my celeryd script which is in:

/etc/init.d/celeryd

is never running or start-up. It's unclear why it isn't though.