Pacemaker and iSCSi

i currently am trying to make a highly available NAS under debian 7. I am using following packages: drbd8-utils iscsitarget iscsitarget-dkms pacemaker corosync openais

everything works fine without pacemaker (so i'll take it's not a conf error)

When i put everything on pacemaker, everything works until i reboot one of the nodes. here is my pacemaker config :

node NAS-1
node NAS-2
primitive nas_ip ocf:heartbeat:IPaddr2 \
    params ip="192.168.152.210" cidr_netmask="255.255.255.0"
primitive p_drbd ocf:linbit:drbd \
    params drbd_resource="nas" \
    op monitor interval="29" role="Master" \
    op monitor interval="31" role="Slave"
primitive p_iscsitarget ocf:heartbeat:iSCSITarget \
    params iqn="iqn.2015.01.net.utopia:nas" tid="1" \
    op monitor interval="10s"
group g_iscsi nas_ip p_iscsitarget
ms ms_drbd p_drbd \
    meta master-max="1" master-node-max="1" clone-max="2" clone-node-max="1" notify="true"
colocation nas inf: g_iscsi ms_drbd:Master
order o_drbd inf: ms_drbd:promote g_iscsi:start
property $id="cib-bootstrap-options" \
    dc-version="1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff" \
    cluster-infrastructure="openais" \
    expected-quorum-votes="2" \
    stonith-enabled="false" \
    no-quorum-policy="ignore" \
    default-resource-stickiness="1"
crm(live)configure#

Here is the following error :

root@NAS-1:~# crm_mon -1
============
Last updated: Wed Jan  7 16:02:53 2015
Last change: Wed Jan  7 15:57:51 2015 via cibadmin on NAS-1
Stack: openais
Current DC: NAS-2 - partition with quorum
Version: 1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff
2 Nodes configured, 2 expected votes
4 Resources configured.
============
Online: [ NAS-1 NAS-2 ]

Master/Slave Set: ms_drbd [p_drbd]
    Masters: [ NAS-2 ]
    Slaves: [ NAS-1 ]
Resource Group: g_iscsi
    nas_ip     (ocf::heartbeat:IPaddr2):       Started NAS-2
    p_iscsitarget      (ocf::heartbeat:iSCSITarget):   Started NAS-2 (unmanaged) FAILED

Failed actions:
    p_iscsitarget_stop_0 (node=NAS-2, call=16, rc=5, status=complete): not installed
root@NAS-1:~#

Note: there is indeed not the iSCSi Logical Unit configured in the NAS, currently in testing phase on VMs, but i had the exact same error with it on my previous test

Could someone help me pinpoint/correct that error please? I guess I'm forgetting something very stupid ...

Thanks in advance!

PS : my conf files for other things : http://ift.tt/1sbcVQN (/etc/drbd.d/*) http://ift.tt/1tPg58h (/etc/iet/ietd.conf)