Could not initialize storage for namespace

Operations Configuration
1

i use the 3.6.0 community version and my config i the following

service {
	user root
	group root
	paxos-single-replica-limit 1 # Number of nodes where the replica count is automatically reduced to 1.
	pidfile /var/run/aerospike/asd.pid
	service-threads 4
	transaction-queues 4
	transaction-threads-per-queue 4
	proto-fd-max 15000
}

logging {
	# Log file must be an absolute path.
	file /var/log/aerospike/aerospike.log {
		context any info
	}
}

network {
	service {
		address any
		port 3000
	}

	heartbeat {
                mode mesh
                port 3002 # Heartbeat port for this node.          

		# To use unicast-mesh heartbeats, remove the 3 lines above, and see
		# aerospike_mesh.conf for alternative.

		interval 150
		timeout 10
	}

	fabric {
		port 3001
	}

	info {
		port 3003
	}
}

namespace push {
	replication-factor 2
	memory-size 60G

	storage-engine device {
		device /dev/sdb1
		write-block-size 128K
	}
}

but it failed with the following message

Jun 29 2016 09:03:17 GMT: WARNING (drv_ssd): (drv_ssd.c::3902) unable to open device /dev/sdb1: Invalid argument
Jun 29 2016 09:03:17 GMT: WARNING (drv_ssd): (drv_ssd.c::4104) ns push can't initialize devices
Jun 29 2016 09:03:17 GMT: CRITICAL (storage): (storage.c:as_storage_init:80) could not initialize storage for namespace push
Jun 29 2016 09:03:17 GMT: WARNING (as): (signal.c::94) SIGABRT received, aborting Aerospike Community Edition build 3.6.0 os el6
Jun 29 2016 09:03:17 GMT: WARNING (as): (signal.c::96) stacktrace: found 9 frames
2
  1. Was this device previously used by an Aerospike namespace by a different name?
  2. Are you trying to rename a namespace?