RHEL 7 High Availability クラスターで、nfsserver リソースの nfs_shared_infodir として使用されるファイルシステムリソースが "ERROR: Couldn't unmount /<path>/rpc_pipefs; trying cleanup with TERM" で停止に失敗する

Issue

• NFS をエクスポートする pacemaker リソースグループが正常に停止しません。
• pacemaker クラスターで NFS エクスポートリソースグループを停止できません。
• NFS サービスを再配置しようとすると、ノードが再起動します

May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [ umount: /var/lib/nfs/rpc_pipefs: target is busy. ]
May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [         (In some cases useful info about processes that use ]
May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [          the device is found by lsof(8) or fuser(1)) ]
May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [ umount: /var/lib/nfs: target is busy. ]
May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [         (In some cases useful info about processes that use ]
May 31 14:40:46 node1 lrmd[9361]:  notice: nfs-daemon_stop_0:69957:stderr [          the device is found by lsof(8) or fuser(1)) ]
May 31 14:41:41 node1 Filesystem(iongxfs)[70546]: INFO: No processes on /nfs/.nfs_shared_infodir/rpc_pipefs were signalled. force_unmount is set to 'safe'
May 31 14:41:42 node1 Filesystem(iongxfs)[70546]: ERROR: Couldn't unmount /nfs/.nfs_shared_infodir/rpc_pipefs; trying cleanup with TERM
May 31 14:41:42 node1 Filesystem(iongxfs)[70546]: INFO: No processes on /nfs/.nfs_shared_infodir/rpc_pipefs were signalled. force_unmount is set to 'safe'
May 31 14:41:43 node1 Filesystem(iongxfs)[70546]: ERROR: Couldn't unmount /nfs/.nfs_shared_infodir/rpc_pipefs; trying cleanup with KILL
May 31 14:41:44 node1 Filesystem(iongxfs)[70546]: INFO: No processes on /nfs/.nfs_shared_infodir/rpc_pipefs were signalled. force_unmount is set to 'safe'
May 31 14:41:45 node1 Filesystem(iongxfs)[70546]: ERROR: Couldn't unmount /nfs/.nfs_shared_infodir/rpc_pipefs; trying cleanup with KILL
May 31 14:41:46 node1 Filesystem(iongxfs)[70546]: INFO: No processes on /nfs/.nfs_shared_infodir/rpc_pipefs were signalled. force_unmount is set to 'safe'
May 31 14:41:47 node1 lrmd[9361]: warning: iongxfs_stop_0 process (PID 70546) timed out
May 31 14:41:47 node1 lrmd[9361]: warning: iongxfs_stop_0:70546 - timed out after 60000ms