SendArp

#!/bin/sh
#
#
#	Copyright (c) 2006, Huang Zhen <zhen.huang@gmail.com>
#	Converting original heartbeat RA to OCF RA.
#
#	Copyright (C) 2004 Horms <horms@verge.net.au>
#
#       Based on IPaddr2: Copyright (C) 2003 Tuomo Soini <tis@foobar.fi>
#
# 	License:      GNU General Public License (GPL)
# 	Support:      users@clusterlabs.org
#
#	This script send out gratuitous Arp for an IP address
#
#       It can be used _instead_ of the IPaddr2 or IPaddr resource
#       to send gratuitous arp for an IP address on a given interface, 
#       without adding the address to that interface. I.e. if for
#       some reason you want to send gratuitous arp for addresses
#       managed by IPaddr2 or IPaddr on an additional interface.
#
#	OCF parameters are as below:
#		OCF_RESKEY_ip
#		OCF_RESKEY_nic
#
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# Further, this software is distributed without any warranty that it is
# free of the rightful claim of any third person regarding infringement
# or the like.  Any license provided herein, whether implied or
# otherwise, applies only to this software file.  Patent licenses, if
# any, provided herein do not apply to combinations of this program with
# other software, or any other product whatsoever.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
#

#######################################################################
# Initialization:

: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs

# Parameter defaults

OCF_RESKEY_ip_default=""
OCF_RESKEY_nic_default=""
OCF_RESKEY_background_default="true"

: ${OCF_RESKEY_ip=${OCF_RESKEY_ip_default}}
: ${OCF_RESKEY_nic=${OCF_RESKEY_nic_default}}
: ${OCF_RESKEY_background=${OCF_RESKEY_background_default}}

SENDARP=$HA_BIN/send_arp
SENDARPPIDDIR=${HA_RSCTMP}

BASEIP="$OCF_RESKEY_ip"
INTERFACE="$OCF_RESKEY_nic"
RESIDUAL=""
SENDARPPIDFILE="$SENDARPPIDDIR/send_arp-$BASEIP"
BACKGROUND=${OCF_RESKEY_background}

# Set default values

	: ${ARP_INTERVAL_MS=200}	# milliseconds between ARPs
	: ${ARP_REPEAT=5}		# repeat count
	: ${ARP_BACKGROUND=$BACKGROUND}	# no to run in foreground
	: ${ARP_NETMASK=ffffffffffff}	# netmask for ARP

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

sendarp_meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="SendArp">
<version>1.0</version>

<longdesc lang="en">
This RA can be used _instead_ of the IPaddr2 or IPaddr RA to
send gratuitous ARP for an IP address on a given interface, 
without adding the address to that interface.  For example,
if for some reason you wanted to send gratuitous ARP for
addresses managed by IPaddr2 or IPaddr on an additional
interface.
</longdesc>
<shortdesc lang="en">Broadcasts unsolicited ARP announcements</shortdesc>

<parameters>
<parameter name="ip" unique="0" required="1">
<longdesc lang="en">
The IP address for sending ARP packet.
</longdesc>
<shortdesc lang="en">IP address</shortdesc>
<content type="string" default="${OCF_RESKEY_ip_default}" />
</parameter>

<parameter name="nic" unique="0" required="1">
<longdesc lang="en">
The NIC for sending ARP packet.
</longdesc>
<shortdesc lang="en">NIC</shortdesc>
<content type="string" default="${OCF_RESKEY_nic_default}" />
</parameter>

<parameter name="background" unique="0" required="0">
<longdesc lang="en">
Send ARPs in background. Set to false if you want to test if
sending ARPs succeeded.
</longdesc>
<shortdesc lang="en">Send ARPs in background</shortdesc>
<content type="boolean" default="${OCF_RESKEY_background_default}" />
</parameter>

</parameters>

<actions>
<action name="start"   timeout="20s" />
<action name="stop"    timeout="20s" />
<action name="monitor" depth="0"  timeout="20s" interval="10s" />
<action name="meta-data"  timeout="5s" />
<action name="validate-all"  timeout="20s" />
</actions>
</resource-agent>
END
}

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

sendarp_usage() {
	cat <<END
usage: $0 {start|stop|monitor|validate-all|meta-data}

Expects to have a fully populated OCF RA-compliant environment set.
END
}

#
#	Send gratuitous arp
#
sendarp_start() {
    local rc

    sendarp_validate
    if [ $? = $OCF_ERR_CONFIGURED ]; then
	return $OCF_ERR_CONFIGURED
    fi
    
    sendarp_monitor
    if [ $? = $OCF_SUCCESS ]; then
	return $OCF_SUCCESS
    fi
    
    [ -r ${HA_CONFDIR}/arp_config ] && . ${HA_CONFDIR}/arp_config
    if [ -r "${HA_CONFDIR}/arp_config:${TARGET_INTERFACE}" ]; then
	. "${HA_CONFDIR}/arp_config:${TARGET_INTERFACE}"
    fi


    ARGS="-i $ARP_INTERVAL_MS -r $ARP_REPEAT -p $SENDARPPIDFILE $INTERFACE $BASEIP auto $BASEIP $ARP_NETMASK"
    ocf_log debug "$SENDARP $ARGS"

    rc=$OCF_SUCCESS
    if ocf_is_true $ARP_BACKGROUND; then
	# not possible to check the status without wait! we can
	# just log the outcome
	# and wait-ing would be equal to not running in
	# background
	($SENDARP $ARGS ||
	    ocf_exit_reason "Could not send gratuitous arps") &
    else
	$SENDARP $ARGS || {
	    ocf_exit_reason "Could not send gratuitous arps"
	    rc=$OCF_ERR_GENERIC
	}
    fi

    if [ $rc -eq $OCF_SUCCESS ]; then
	ha_pseudo_resource SendArp_${OCF_RESOURCE_INSTANCE} start
    fi
    return $rc
}

#
#	Stop sending gratuitous arp
#
sendarp_stop() {
    sendarp_monitor
    if [ $? -eq $OCF_NOT_RUNNING ]; then
	return $OCF_SUCCESS
    fi
 
    rc=$OCF_SUCCESS
    
    if
	[ -f "$SENDARPPIDFILE" ]
    then
	kill `cat "$SENDARPPIDFILE"`
	rc=$?
	case $rc in
	    0)
		ocf_log info "killed previously running send_arp for $BASEIP"
		rm -f "$SENDARPPIDFILE"
		rc=$OCF_SUCCESS
		;;
	    *)
		ocf_log warn "Could not kill previously running send_arp for $BASEIP"
		rc=$OCF_ERR_GENERIC
		;;
	esac
    fi

    case $rc in
	$OCF_SUCCESS)
	    ocf_log info "SendArp for $BASEIP/$INTERFACE released"
	    ha_pseudo_resource SendArp_${OCF_RESOURCE_INSTANCE} stop
	    ;;
	*)
	    ocf_log warn "SendArp for $BASEIP/$INTERFACE NOT released"
	    ;;
    esac
    return $rc
}
#
sendarp_monitor() {
    if [ -f "$SENDARPPIDFILE" ]; then
    	return $OCF_SUCCESS
    fi
    ha_pseudo_resource SendArp_${OCF_RESOURCE_INSTANCE} monitor
}

sendarp_validate() {
    if [ -z "$INTERFACE" -o -z "$BASEIP" -o -n "$RESIDUAL" ]
    then
        return $OCF_ERR_CONFIGURED
    fi
    return $OCF_SUCCESS
}

case $__OCF_ACTION in
meta-data)	sendarp_meta_data
		exit $OCF_SUCCESS
		;;
start)		sendarp_start
		;;
stop)		sendarp_stop
		;;
monitor)	sendarp_monitor
		;;
status)		sendarp_monitor
		if [ $? = $OCF_SUCCESS ]; then
			echo "running"
			exit $OCF_SUCCESS;
		else 
			echo "stopped"
			exit $OCF_NOT_RUNNING;
    		fi
    		;;
validate-all)	sendarp_validate
		;;
usage|help)	sendarp_usage
		exit $OCF_SUCCESS
		;;
*)		sendarp_usage
		exit $OCF_ERR_UNIMPLEMENTED
		;;
esac