diff --git a/cmd/zed/agents/zfs_agents.c b/cmd/zed/agents/zfs_agents.c
index a40d59497fbf..47e251a5e760 100644
--- a/cmd/zed/agents/zfs_agents.c
+++ b/cmd/zed/agents/zfs_agents.c
@@ -350,19 +350,3 @@ zfs_agent_fini(void)
 
 	g_zfs_hdl = NULL;
 }
-
-/*
- * In ZED context, all the FMA agents run in the same thread
- * and do not require a unique libzfs instance. Modules should
- * use these stubs.
- */
-libzfs_handle_t *
-__libzfs_init(void)
-{
-	return (g_zfs_hdl);
-}
-
-void
-__libzfs_fini(libzfs_handle_t *hdl)
-{
-}
diff --git a/cmd/zed/agents/zfs_agents.h b/cmd/zed/agents/zfs_agents.h
index 3c9af54c926c..d1a459139b1e 100644
--- a/cmd/zed/agents/zfs_agents.h
+++ b/cmd/zed/agents/zfs_agents.h
@@ -39,13 +39,6 @@ extern int zfs_slm_init(void);
 extern void zfs_slm_fini(void);
 extern void zfs_slm_event(const char *, const char *, nvlist_t *);
 
-/*
- * In ZED context, all the FMA agents run in the same thread
- * and do not require a unique libzfs instance.
- */
-extern libzfs_handle_t *__libzfs_init(void);
-extern void __libzfs_fini(libzfs_handle_t *);
-
 #ifdef	__cplusplus
 }
 #endif
diff --git a/cmd/zed/agents/zfs_diagnosis.c b/cmd/zed/agents/zfs_diagnosis.c
index 49e3e16609e2..6f1f4d0175e6 100644
--- a/cmd/zed/agents/zfs_diagnosis.c
+++ b/cmd/zed/agents/zfs_diagnosis.c
@@ -919,27 +919,27 @@ _zfs_diagnosis_init(fmd_hdl_t *hdl)
 {
 	libzfs_handle_t *zhdl;
 
-	if ((zhdl = __libzfs_init()) == NULL)
+	if ((zhdl = libzfs_init()) == NULL)
 		return;
 
 	if ((zfs_case_pool = uu_list_pool_create("zfs_case_pool",
 	    sizeof (zfs_case_t), offsetof(zfs_case_t, zc_node),
 	    NULL, UU_LIST_POOL_DEBUG)) == NULL) {
-		__libzfs_fini(zhdl);
+		libzfs_fini(zhdl);
 		return;
 	}
 
 	if ((zfs_cases = uu_list_create(zfs_case_pool, NULL,
 	    UU_LIST_DEBUG)) == NULL) {
 		uu_list_pool_destroy(zfs_case_pool);
-		__libzfs_fini(zhdl);
+		libzfs_fini(zhdl);
 		return;
 	}
 
 	if (fmd_hdl_register(hdl, FMD_API_VERSION, &fmd_info) != 0) {
 		uu_list_destroy(zfs_cases);
 		uu_list_pool_destroy(zfs_case_pool);
-		__libzfs_fini(zhdl);
+		libzfs_fini(zhdl);
 		return;
 	}
 
@@ -975,5 +975,5 @@ _zfs_diagnosis_fini(fmd_hdl_t *hdl)
 	uu_list_pool_destroy(zfs_case_pool);
 
 	zhdl = fmd_hdl_getspecific(hdl);
-	__libzfs_fini(zhdl);
+	libzfs_fini(zhdl);
 }
diff --git a/cmd/zed/agents/zfs_mod.c b/cmd/zed/agents/zfs_mod.c
index 5fa74d0cea98..54568e75ad9a 100644
--- a/cmd/zed/agents/zfs_mod.c
+++ b/cmd/zed/agents/zfs_mod.c
@@ -64,7 +64,6 @@
  * trigger the FMA fault that we skipped earlier.
  *
  * ZFS on Linux porting notes:
- *	In lieu of a thread pool, just spawn a thread on demmand.
  *	Linux udev provides a disk insert for both the disk and the partition
  *
  */
@@ -83,6 +82,7 @@
 #include <sys/sunddi.h>
 #include <sys/sysevent/eventdefs.h>
 #include <sys/sysevent/dev.h>
+#include <thread_pool.h>
 #include <pthread.h>
 #include <unistd.h>
 #include "zfs_agents.h"
@@ -97,12 +97,12 @@ typedef void (*zfs_process_func_t)(zpool_handle_t *, nvlist_t *, boolean_t);
 libzfs_handle_t *g_zfshdl;
 list_t g_pool_list;	/* list of unavailable pools at initialization */
 list_t g_device_list;	/* list of disks with asynchronous label request */
+tpool_t *g_tpool;
 boolean_t g_enumeration_done;
-pthread_t g_zfs_tid;
+pthread_t g_zfs_tid;	/* zfs_enum_pools() thread */
 
 typedef struct unavailpool {
 	zpool_handle_t	*uap_zhp;
-	pthread_t	uap_enable_tid;	/* dataset enable thread if activated */
 	list_node_t	uap_node;
 } unavailpool_t;
 
@@ -135,7 +135,6 @@ zfs_unavail_pool(zpool_handle_t *zhp, void *data)
 		unavailpool_t *uap;
 		uap = malloc(sizeof (unavailpool_t));
 		uap->uap_zhp = zhp;
-		uap->uap_enable_tid = 0;
 		list_insert_tail((list_t *)data, uap);
 	} else {
 		zpool_close(zhp);
@@ -512,19 +511,14 @@ zfs_iter_vdev(zpool_handle_t *zhp, nvlist_t *nvl, void *data)
 	(dp->dd_func)(zhp, nvl, dp->dd_islabeled);
 }
 
-static void *
+void
 zfs_enable_ds(void *arg)
 {
 	unavailpool_t *pool = (unavailpool_t *)arg;
 
-	assert(pool->uap_enable_tid = pthread_self());
-
 	(void) zpool_enable_datasets(pool->uap_zhp, NULL, 0);
 	zpool_close(pool->uap_zhp);
-	pool->uap_zhp = NULL;
-
-	/* Note: zfs_slm_fini() will cleanup this pool entry on exit */
-	return (NULL);
+	free(pool);
 }
 
 static int
@@ -559,15 +553,13 @@ zfs_iter_pool(zpool_handle_t *zhp, void *data)
 		for (pool = list_head(&g_pool_list); pool != NULL;
 		    pool = list_next(&g_pool_list, pool)) {
 
-			if (pool->uap_enable_tid != 0)
-				continue;	/* entry already processed */
 			if (strcmp(zpool_get_name(zhp),
 			    zpool_get_name(pool->uap_zhp)))
 				continue;
 			if (zfs_toplevel_state(zhp) >= VDEV_STATE_DEGRADED) {
-				/* send to a background thread; keep on list */
-				(void) pthread_create(&pool->uap_enable_tid,
-				    NULL, zfs_enable_ds, pool);
+				list_remove(&g_pool_list, pool);
+				(void) tpool_dispatch(g_tpool, zfs_enable_ds,
+				    pool);
 				break;
 			}
 		}
@@ -857,7 +849,7 @@ zfs_enum_pools(void *arg)
 int
 zfs_slm_init()
 {
-	if ((g_zfshdl = __libzfs_init()) == NULL)
+	if ((g_zfshdl = libzfs_init()) == NULL)
 		return (-1);
 
 	/*
@@ -869,7 +861,7 @@ zfs_slm_init()
 
 	if (pthread_create(&g_zfs_tid, NULL, zfs_enum_pools, NULL) != 0) {
 		list_destroy(&g_pool_list);
-		__libzfs_fini(g_zfshdl);
+		libzfs_fini(g_zfshdl);
 		return (-1);
 	}
 
@@ -887,19 +879,15 @@ zfs_slm_fini()
 
 	/* wait for zfs_enum_pools thread to complete */
 	(void) pthread_join(g_zfs_tid, NULL);
+	/* destroy the thread pool */
+	if (g_tpool != NULL) {
+		tpool_wait(g_tpool);
+		tpool_destroy(g_tpool);
+	}
 
 	while ((pool = (list_head(&g_pool_list))) != NULL) {
-		/*
-		 * each pool entry has two possibilities
-		 * 1. was made available (so wait for zfs_enable_ds thread)
-		 * 2. still unavailable (just close the pool)
-		 */
-		if (pool->uap_enable_tid)
-			(void) pthread_join(pool->uap_enable_tid, NULL);
-		else if (pool->uap_zhp != NULL)
-			zpool_close(pool->uap_zhp);
-
 		list_remove(&g_pool_list, pool);
+		zpool_close(pool->uap_zhp);
 		free(pool);
 	}
 	list_destroy(&g_pool_list);
@@ -910,7 +898,7 @@ zfs_slm_fini()
 	}
 	list_destroy(&g_device_list);
 
-	__libzfs_fini(g_zfshdl);
+	libzfs_fini(g_zfshdl);
 }
 
 void
diff --git a/cmd/zed/agents/zfs_retire.c b/cmd/zed/agents/zfs_retire.c
index f69c583f0b1f..5a090e32f699 100644
--- a/cmd/zed/agents/zfs_retire.c
+++ b/cmd/zed/agents/zfs_retire.c
@@ -176,6 +176,8 @@ replace_with_spare(fmd_hdl_t *hdl, zpool_handle_t *zhp, nvlist_t *vdev)
 	nvlist_t **spares;
 	uint_t s, nspares;
 	char *dev_name;
+	zprop_source_t source;
+	int ashift;
 
 	config = zpool_get_config(zhp, NULL);
 	if (nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
@@ -189,6 +191,11 @@ replace_with_spare(fmd_hdl_t *hdl, zpool_handle_t *zhp, nvlist_t *vdev)
 	    &spares, &nspares) != 0)
 		return;
 
+	/*
+	 * lookup "ashift" pool property, we may need it for the replacement
+	 */
+	ashift = zpool_get_prop_int(zhp, ZPOOL_PROP_ASHIFT, &source);
+
 	replacement = fmd_nvl_alloc(hdl, FMD_SLEEP);
 
 	(void) nvlist_add_string(replacement, ZPOOL_CONFIG_TYPE,
@@ -207,6 +214,11 @@ replace_with_spare(fmd_hdl_t *hdl, zpool_handle_t *zhp, nvlist_t *vdev)
 		    &spare_name) != 0)
 			continue;
 
+		/* if set, add the "ashift" pool property to the spare nvlist */
+		if (source != ZPROP_SRC_DEFAULT)
+			(void) nvlist_add_uint64(spares[s],
+			    ZPOOL_CONFIG_ASHIFT, ashift);
+
 		(void) nvlist_add_nvlist_array(replacement,
 		    ZPOOL_CONFIG_CHILDREN, &spares[s], 1);
 
@@ -483,7 +495,7 @@ _zfs_retire_init(fmd_hdl_t *hdl)
 	zfs_retire_data_t *zdp;
 	libzfs_handle_t *zhdl;
 
-	if ((zhdl = __libzfs_init()) == NULL)
+	if ((zhdl = libzfs_init()) == NULL)
 		return;
 
 	if (fmd_hdl_register(hdl, FMD_API_VERSION, &fmd_info) != 0) {
@@ -504,7 +516,7 @@ _zfs_retire_fini(fmd_hdl_t *hdl)
 
 	if (zdp != NULL) {
 		zfs_retire_clear_data(hdl, zdp);
-		__libzfs_fini(zdp->zrd_hdl);
+		libzfs_fini(zdp->zrd_hdl);
 		fmd_hdl_free(hdl, zdp, sizeof (zfs_retire_data_t));
 	}
 }
diff --git a/tests/runfiles/linux.run b/tests/runfiles/linux.run
index 9424c80a02cf..0c8f298c6d49 100644
--- a/tests/runfiles/linux.run
+++ b/tests/runfiles/linux.run
@@ -464,7 +464,7 @@ tags = ['functional', 'exec']
 
 [tests/functional/fault]
 tests = ['auto_online_001_pos', 'auto_replace_001_pos', 'auto_spare_001_pos',
-    'auto_spare_002_pos.ksh']
+    'auto_spare_002_pos', 'auto_spare_ashift', 'auto_spare_multiple']
 tags = ['functional', 'fault']
 
 [tests/functional/features/async_destroy]
diff --git a/tests/zfs-tests/include/blkdev.shlib b/tests/zfs-tests/include/blkdev.shlib
index 876c843561b8..28ac1052c3d0 100644
--- a/tests/zfs-tests/include/blkdev.shlib
+++ b/tests/zfs-tests/include/blkdev.shlib
@@ -353,16 +353,35 @@ function insert_disk #disk scsi_host
 
 #
 # Load scsi_debug module with specified parameters
+# $blksz can be either one of: < 512b | 512e | 4Kn >
 #
-function load_scsi_debug # dev_size_mb add_host num_tgts max_luns
+function load_scsi_debug # dev_size_mb add_host num_tgts max_luns blksz
 {
 	typeset devsize=$1
 	typeset hosts=$2
 	typeset tgts=$3
 	typeset luns=$4
+	typeset blksz=$5
 
 	[[ -z $devsize ]] || [[ -z $hosts ]] || [[ -z $tgts ]] || \
-	    [[ -z $luns ]] && log_fail "Arguments invalid or missing"
+	    [[ -z $luns ]] || [[ -z $blksz ]] && \
+	    log_fail "Arguments invalid or missing"
+
+	case "$5" in
+		'512b')
+			typeset sector=512
+			typeset blkexp=0
+		;;
+		'512e')
+			typeset sector=512
+			typeset blkexp=3
+		;;
+		'4Kn')
+			typeset sector=4096
+			typeset blkexp=0
+		;;
+		*) log_fail "Unsupported blksz value: $5" ;;
+	esac
 
 	if is_linux; then
 		modprobe -n scsi_debug
@@ -375,7 +394,8 @@ function load_scsi_debug # dev_size_mb add_host num_tgts max_luns
 			log_fail "scsi_debug module already installed"
 		else
 			log_must modprobe scsi_debug dev_size_mb=$devsize \
-			    add_host=$hosts num_tgts=$tgts max_luns=$luns
+			    add_host=$hosts num_tgts=$tgts max_luns=$luns \
+			    sector_size=$sector physblk_exp=$blkexp
 			block_device_wait
 			lsscsi | egrep scsi_debug > /dev/null
 			if (($? == 1)); then
@@ -385,6 +405,16 @@ function load_scsi_debug # dev_size_mb add_host num_tgts max_luns
 	fi
 }
 
+#
+# Unload scsi_debug module, if needed.
+#
+function unload_scsi_debug
+{
+	if lsmod | grep scsi_debug >/dev/null; then
+		log_must modprobe -r scsi_debug
+	fi
+}
+
 #
 # Get scsi_debug device name.
 # Returns basename of scsi_debug device (for example "sdb").
diff --git a/tests/zfs-tests/include/libtest.shlib b/tests/zfs-tests/include/libtest.shlib
index 6b1658c1b6ce..cc9fddd415a4 100644
--- a/tests/zfs-tests/include/libtest.shlib
+++ b/tests/zfs-tests/include/libtest.shlib
@@ -3158,13 +3158,25 @@ function zed_stop
 	if [[ -f ${ZEDLET_DIR}/zed.pid ]]; then
 		zedpid=$(cat ${ZEDLET_DIR}/zed.pid)
 		kill $zedpid
-		wait $zedpid
+		while ps -p $zedpid > /dev/null; do
+			sleep 1
+		done
 		rm -f ${ZEDLET_DIR}/zed.pid
 	fi
-
 	return 0
 }
 
+#
+# Drain all zevents
+#
+function zed_events_drain
+{
+	while [ $(zpool events -H | wc -l) -ne 0 ]; do
+		sleep 1
+		zpool events -c >/dev/null
+	done
+}
+
 #
 # Check is provided device is being active used as a swap device.
 #
diff --git a/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/cleanup.ksh b/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/cleanup.ksh
index 4477e54027fb..99c51351c5c8 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/cleanup.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/cleanup.ksh
@@ -27,7 +27,7 @@ if is_linux; then
 	for SDDEVICE in $(get_debug_device); do
 		unplug $SDDEVICE
 	done
-	modprobe -r scsi_debug
+	unload_scsi_debug
 fi
 
 log_pass
diff --git a/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/setup.ksh b/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/setup.ksh
index 4dbf8965dc6b..59b8764ced84 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/setup.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zpool_reopen/setup.ksh
@@ -22,7 +22,7 @@ verify_runnable "global"
 
 # Create scsi_debug devices for the reopen tests
 if is_linux; then
-	load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS
+	load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS '512b'
 else
 	log_unsupported "scsi debug module unsupported"
 fi
diff --git a/tests/zfs-tests/tests/functional/fault/Makefile.am b/tests/zfs-tests/tests/functional/fault/Makefile.am
index 436f3e8be719..ef4380835c37 100644
--- a/tests/zfs-tests/tests/functional/fault/Makefile.am
+++ b/tests/zfs-tests/tests/functional/fault/Makefile.am
@@ -6,4 +6,6 @@ dist_pkgdata_SCRIPTS = \
 	auto_online_001_pos.ksh \
 	auto_replace_001_pos.ksh \
 	auto_spare_001_pos.ksh \
-	auto_spare_002_pos.ksh
+	auto_spare_002_pos.ksh \
+	auto_spare_ashift.ksh \
+	auto_spare_multiple.ksh
diff --git a/tests/zfs-tests/tests/functional/fault/auto_online_001_pos.ksh b/tests/zfs-tests/tests/functional/fault/auto_online_001_pos.ksh
index 0f6e38ac2271..beff5dc87ce1 100755
--- a/tests/zfs-tests/tests/functional/fault/auto_online_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/fault/auto_online_001_pos.ksh
@@ -54,9 +54,8 @@ fi
 
 function cleanup
 {
-	#online last disk before fail
-	insert_disk $offline_disk $host
-	poolexists $TESTPOOL && destroy_pool $TESTPOOL
+	destroy_pool $TESTPOOL
+	unload_scsi_debug
 }
 
 log_assert "Testing automated auto-online FMA test"
@@ -65,8 +64,8 @@ log_onexit cleanup
 
 # If using the default loop devices, need a scsi_debug device for auto-online
 if is_loop_device $DISK1; then
-	SD=$(lsscsi | nawk '/scsi_debug/ {print $6; exit}')
-	SDDEVICE=$(echo $SD | nawk -F / '{print $3}')
+	load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS '512b'
+	SDDEVICE=$(get_debug_device)
 	SDDEVICE_ID=$(get_persistent_disk_name $SDDEVICE)
 	autoonline_disks="$SDDEVICE"
 else
diff --git a/tests/zfs-tests/tests/functional/fault/auto_replace_001_pos.ksh b/tests/zfs-tests/tests/functional/fault/auto_replace_001_pos.ksh
index 40a680a9bb02..8e48b2ab4371 100755
--- a/tests/zfs-tests/tests/functional/fault/auto_replace_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/fault/auto_replace_001_pos.ksh
@@ -57,27 +57,23 @@ fi
 
 function setup
 {
-	lsmod | egrep scsi_debug > /dev/null
-	if (($? == 1)); then
-		load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS
-	fi
+	load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS '512b'
+	SD=$(get_debug_device)
+	SDDEVICE_ID=$(get_persistent_disk_name $SD)
 	# Register vdev_id alias rule for scsi_debug device to create a
 	# persistent path
-	SD=$(lsscsi | nawk '/scsi_debug/ {print $6; exit}' \
-	    | nawk -F / '{print $3}')
-	SDDEVICE_ID=$(get_persistent_disk_name $SD)
 	log_must eval "echo "alias scsidebug /dev/disk/by-id/$SDDEVICE_ID" \
 	    >> $VDEVID_CONF"
 	block_device_wait
-
-	SDDEVICE=$(udevadm info -q all -n $DEV_DSKDIR/$SD | egrep ID_VDEV \
-	    | nawk '{print $2; exit}' | nawk -F = '{print $2; exit}')
+	SDDEVICE=$(udevadm info -q all -n $DEV_DSKDIR/$SD \
+	    | awk -F'=' '/ID_VDEV=/{print $2; exit}')
 	[[ -z $SDDEVICE ]] && log_fail "vdev rule was not registered properly"
 }
 
 function cleanup
 {
-	poolexists $TESTPOOL && destroy_pool $TESTPOOL
+	destroy_pool $TESTPOOL
+	unload_scsi_debug
 }
 
 log_assert "Testing automated auto-replace FMA test"
@@ -112,7 +108,7 @@ log_must zpool export -F $TESTPOOL
 # Offline disk
 remove_disk $SD
 block_device_wait
-log_must modprobe -r scsi_debug
+unload_scsi_debug
 
 # Reimport pool with drive missing
 log_must zpool import $TESTPOOL
diff --git a/tests/zfs-tests/tests/functional/fault/auto_spare_001_pos.ksh b/tests/zfs-tests/tests/functional/fault/auto_spare_001_pos.ksh
index 82f7f4834ce6..b6af1a3f40f8 100755
--- a/tests/zfs-tests/tests/functional/fault/auto_spare_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/fault/auto_spare_001_pos.ksh
@@ -42,7 +42,7 @@ verify_runnable "both"
 function cleanup
 {
 	log_must zinject -c all
-	poolexists $TESTPOOL && destroy_pool $TESTPOOL
+	destroy_pool $TESTPOOL
 	rm -f $VDEV_FILES $SPARE_FILE
 }
 
@@ -50,6 +50,9 @@ log_assert "Testing automated auto-spare FMA test"
 
 log_onexit cleanup
 
+# Clear events from previous runs
+zed_events_drain
+
 TESTFILE="/$TESTPOOL/$TESTFS/testfile"
 
 for type in "mirror" "raidz" "raidz2"; do
diff --git a/tests/zfs-tests/tests/functional/fault/auto_spare_002_pos.ksh b/tests/zfs-tests/tests/functional/fault/auto_spare_002_pos.ksh
index f0ddac35cfed..cfa748d304b2 100755
--- a/tests/zfs-tests/tests/functional/fault/auto_spare_002_pos.ksh
+++ b/tests/zfs-tests/tests/functional/fault/auto_spare_002_pos.ksh
@@ -42,7 +42,7 @@ verify_runnable "both"
 function cleanup
 {
 	log_must zinject -c all
-	poolexists $TESTPOOL && destroy_pool $TESTPOOL
+	destroy_pool $TESTPOOL
 	rm -f $VDEV_FILES $SPARE_FILE
 }
 
@@ -50,6 +50,9 @@ log_assert "Testing automated auto-spare FMA test"
 
 log_onexit cleanup
 
+# Clear events from previous runs
+zed_events_drain
+
 TESTFILE="/$TESTPOOL/$TESTFS/testfile"
 
 for type in "mirror" "raidz" "raidz2"; do
@@ -65,8 +68,14 @@ for type in "mirror" "raidz" "raidz2"; do
 	log_must dd if=/dev/urandom of=$TESTFILE bs=1M count=16
 
 	# 4. Inject CHECKSUM ERRORS on read with a zinject error handler
+	# NOTE: checksum events are ratelimited to max 5 per second, ZED needs
+	#       10 to kick in a spare
 	log_must zinject -d $FAULT_FILE -e corrupt -f 50 -T read $TESTPOOL
 	log_must cp $TESTFILE /dev/null
+	log_must sleep 1
+	log_must cp $TESTFILE /dev/null
+	log_must sleep 1
+	log_must cp $TESTFILE /dev/null
 
 	# 5. Verify the ZED kicks in a hot spare and expected pool/device status
 	log_note "Wait for ZED to auto-spare"
diff --git a/tests/zfs-tests/tests/functional/fault/auto_spare_ashift.ksh b/tests/zfs-tests/tests/functional/fault/auto_spare_ashift.ksh
new file mode 100755
index 000000000000..e9857518ed8a
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/fault/auto_spare_ashift.ksh
@@ -0,0 +1,101 @@
+#!/bin/ksh -p
+
+#
+# CDDL HEADER START
+#
+# This file and its contents are supplied under the terms of the
+# Common Development and Distribution License ("CDDL"), version 1.0.
+# You may only use this file in accordance with the terms of version
+# 1.0 of the CDDL.
+#
+# A full copy of the text of the CDDL should have accompanied this
+# source.  A copy of the CDDL is also available via the Internet at
+# http://www.illumos.org/license/CDDL.
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2017 by Intel Corporation. All rights reserved.
+# Copyright 2017, loli10K <ezomori.nozomu@gmail.com>. All rights reserved.
+#
+
+. $STF_SUITE/include/libtest.shlib
+. $STF_SUITE/include/math.shlib
+. $STF_SUITE/tests/functional/fault/fault.cfg
+
+#
+# DESCRIPTION:
+# Testing Fault Management Agent ZED Logic - Automated Auto-Spare Test when
+# drive is faulted and a custom ashift value needs to be provided to replace it.
+#
+# STRATEGY:
+# 1. Create a pool from 512b devices and set "ashift" pool property accordingly
+# 2. Add one 512e spare device (4Kn would generate IO errors on replace)
+# 3. Inject IO errors with a zinject error handler
+# 4. Start a scrub
+# 5. Verify the ZED kicks in the hot spare and expected pool/device status
+# 6. Clear the fault
+# 7. Verify the hot spare is available and expected pool/device status
+#
+
+verify_runnable "both"
+
+function cleanup
+{
+	log_must zinject -c all
+	destroy_pool $TESTPOOL
+	unload_scsi_debug
+	rm -f $SAFE_DEVICE $FAIL_DEVICE
+}
+
+log_assert "ZED should replace a device using the configured ashift property"
+log_onexit cleanup
+
+# Clear events from previous runs
+zed_events_drain
+
+SAFE_DEVICE="$TEST_BASE_DIR/safe-dev"
+FAIL_DEVICE="$TEST_BASE_DIR/fail-dev"
+
+# 1. Create a pool from 512b devices and set "ashift" pool property accordingly
+for vdev in $SAFE_DEVICE $FAIL_DEVICE; do
+	truncate -s $SPA_MINDEVSIZE $vdev
+done
+log_must zpool create -f $TESTPOOL mirror $SAFE_DEVICE $FAIL_DEVICE
+# NOTE: file VDEVs should be added as 512b devices, verify this "just in case"
+for vdev in $SAFE_DEVICE $FAIL_DEVICE; do
+	verify_eq "9" "$(zdb -e -l $vdev | awk '/ashift: /{print $2}')" "ashift"
+done
+log_must zpool set ashift=9 $TESTPOOL
+
+# 2. Add one 512e spare device (4Kn would generate IO errors on replace)
+# NOTE: must be larger than the existing 512b devices, add 32m of fudge
+load_scsi_debug $(($SPA_MINDEVSIZE/1024/1024+32)) $SDHOSTS $SDTGTS $SDLUNS '512e'
+SPARE_DEVICE=$(get_debug_device)
+log_must_busy zpool add $TESTPOOL spare $SPARE_DEVICE
+
+# 3. Inject IO errors with a zinject error handler
+log_must zinject -d $FAIL_DEVICE -e io -T all -f 100 $TESTPOOL
+
+# 4. Start a scrub
+log_must zpool scrub $TESTPOOL
+
+# 5. Verify the ZED kicks in a hot spare and expected pool/device status
+log_note "Wait for ZED to auto-spare"
+log_must wait_vdev_state $TESTPOOL $FAIL_DEVICE "FAULTED" 60
+log_must wait_vdev_state $TESTPOOL $SPARE_DEVICE "ONLINE" 60
+log_must wait_hotspare_state $TESTPOOL $SPARE_DEVICE "INUSE"
+log_must check_state $TESTPOOL "" "DEGRADED"
+
+# 6. Clear the fault
+log_must zinject -c all
+log_must zpool clear $TESTPOOL $FAIL_DEVICE
+
+# 7. Verify the hot spare is available and expected pool/device status
+log_must wait_vdev_state $TESTPOOL $FAIL_DEVICE "ONLINE" 60
+log_must wait_hotspare_state $TESTPOOL $SPARE_DEVICE "AVAIL"
+log_must is_pool_resilvered $TESTPOOL
+log_must check_state $TESTPOOL "" "ONLINE"
+
+log_pass "ZED successfully replaces a device using the configured ashift property"
diff --git a/tests/zfs-tests/tests/functional/fault/auto_spare_multiple.ksh b/tests/zfs-tests/tests/functional/fault/auto_spare_multiple.ksh
new file mode 100755
index 000000000000..8650ceff7d16
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/fault/auto_spare_multiple.ksh
@@ -0,0 +1,152 @@
+#!/bin/ksh -p
+
+#
+# CDDL HEADER START
+#
+# This file and its contents are supplied under the terms of the
+# Common Development and Distribution License ("CDDL"), version 1.0.
+# You may only use this file in accordance with the terms of version
+# 1.0 of the CDDL.
+#
+# A full copy of the text of the CDDL should have accompanied this
+# source.  A copy of the CDDL is also available via the Internet at
+# http://www.illumos.org/license/CDDL.
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2017 by Intel Corporation. All rights reserved.
+# Copyright 2017, loli10K <ezomori.nozomu@gmail.com>. All rights reserved.
+#
+
+. $STF_SUITE/include/libtest.shlib
+. $STF_SUITE/tests/functional/fault/fault.cfg
+
+#
+# DESCRIPTION:
+# Testing Fault Management Agent ZED Logic - Automated Auto-Spare Test when
+# multiple drives are faulted.
+#
+# STRATEGY:
+# 1. Create a pool with two hot spares
+# 2. Inject IO ERRORS with a zinject error handler on the first device
+# 3. Start a scrub
+# 4. Verify the ZED kicks in a hot spare and expected pool/device status
+# 5. Inject IO ERRORS on a second device
+# 6. Start a scrub
+# 7. Verify the ZED kicks in a second hot spare
+# 8. Clear the fault on both devices
+# 9. Verify the hot spares are available and expected pool/device status
+# 10. Rinse and repeat, this time faulting both devices at the same time
+#
+
+verify_runnable "both"
+
+function cleanup
+{
+	log_must zinject -c all
+	destroy_pool $TESTPOOL
+	rm -f $DATA_DEVS $SPARE_DEVS
+}
+
+log_assert "ZED should be able to handle multiple faulted devices"
+log_onexit cleanup
+
+# Clear events from previous runs
+zed_events_drain
+
+FAULT_DEV1="$TEST_BASE_DIR/fault-dev1"
+FAULT_DEV2="$TEST_BASE_DIR/fault-dev2"
+SAFE_DEV1="$TEST_BASE_DIR/safe-dev1"
+SAFE_DEV2="$TEST_BASE_DIR/safe-dev2"
+DATA_DEVS="$FAULT_DEV1 $FAULT_DEV2 $SAFE_DEV1 $SAFE_DEV2"
+SPARE_DEV1="$TEST_BASE_DIR/spare-dev1"
+SPARE_DEV2="$TEST_BASE_DIR/spare-dev2"
+SPARE_DEVS="$SPARE_DEV1 $SPARE_DEV2"
+
+for type in "mirror" "raidz" "raidz2" "raidz3"; do
+	# 1. Create a pool with two hot spares
+	truncate -s $SPA_MINDEVSIZE $DATA_DEVS $SPARE_DEVS
+	log_must zpool create -f $TESTPOOL $type $DATA_DEVS spare $SPARE_DEVS
+
+	# 2. Inject IO ERRORS with a zinject error handler on the first device
+	log_must zinject -d $FAULT_DEV1 -e io -T all -f 100 $TESTPOOL
+
+	# 3. Start a scrub
+	log_must zpool scrub $TESTPOOL
+
+	# 4. Verify the ZED kicks in a hot spare and expected pool/device status
+	log_note "Wait for ZED to auto-spare"
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV1 "FAULTED" 60
+	log_must wait_vdev_state $TESTPOOL $SPARE_DEV1 "ONLINE" 60
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV1 "INUSE"
+	log_must check_state $TESTPOOL "" "DEGRADED"
+
+	# 5. Inject IO ERRORS on a second device
+	log_must zinject -d $FAULT_DEV2 -e io -T all -f 100 $TESTPOOL
+
+	# 6. Start a scrub
+	while is_pool_scrubbing $TESTPOOL || is_pool_resilvering $TESTPOOL; do
+		sleep 1
+	done
+	log_must zpool scrub $TESTPOOL
+
+	# 7. Verify the ZED kicks in a second hot spare
+	log_note "Wait for ZED to auto-spare"
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV2 "FAULTED" 60
+	log_must wait_vdev_state $TESTPOOL $SPARE_DEV2 "ONLINE" 60
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV2 "INUSE"
+	log_must check_state $TESTPOOL "" "DEGRADED"
+
+	# 8. Clear the fault on both devices
+	log_must zinject -c all
+	log_must zpool clear $TESTPOOL $FAULT_DEV1
+	log_must zpool clear $TESTPOOL $FAULT_DEV2
+
+	# 9. Verify the hot spares are available and expected pool/device status
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV1 "ONLINE" 60
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV2 "ONLINE" 60
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV1 "AVAIL"
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV2 "AVAIL"
+	log_must check_state $TESTPOOL "" "ONLINE"
+
+	# Cleanup
+	cleanup
+done
+
+# Rinse and repeat, this time faulting both devices at the same time
+# NOTE: "raidz" is exluded since it cannot survive 2 faulted devices
+# NOTE: "mirror" is a 4-way mirror here and should survive this test
+for type in "mirror" "raidz2" "raidz3"; do
+	# 1. Create a pool with two hot spares
+	truncate -s $SPA_MINDEVSIZE $DATA_DEVS $SPARE_DEVS
+	log_must zpool create -f $TESTPOOL $type $DATA_DEVS spare $SPARE_DEVS
+
+	# 2. Inject IO ERRORS with a zinject error handler on two devices
+	log_must eval "zinject -d $FAULT_DEV1 -e io -T all -f 100 $TESTPOOL &"
+	log_must eval "zinject -d $FAULT_DEV2 -e io -T all -f 100 $TESTPOOL &"
+
+	# 3. Start a scrub
+	log_must zpool scrub $TESTPOOL
+
+	# 4. Verify the ZED kicks in two hot spares and expected pool/device status
+	log_note "Wait for ZED to auto-spare"
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV1 "FAULTED" 60
+	log_must wait_vdev_state $TESTPOOL $FAULT_DEV2 "FAULTED" 60
+	log_must wait_vdev_state $TESTPOOL $SPARE_DEV1 "ONLINE" 60
+	log_must wait_vdev_state $TESTPOOL $SPARE_DEV2 "ONLINE" 60
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV1 "INUSE"
+	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV2 "INUSE"
+	log_must check_state $TESTPOOL "" "DEGRADED"
+
+	# 5. Clear the fault on both devices
+	log_must zinject -c all
+	log_must zpool clear $TESTPOOL $FAULT_DEV1
+	log_must zpool clear $TESTPOOL $FAULT_DEV2
+
+	# Cleanup
+	cleanup
+done
+
+log_pass "ZED successfully handles multiple faulted devices"
diff --git a/tests/zfs-tests/tests/functional/fault/cleanup.ksh b/tests/zfs-tests/tests/functional/fault/cleanup.ksh
index 82e379b0d085..9d354f30e709 100755
--- a/tests/zfs-tests/tests/functional/fault/cleanup.ksh
+++ b/tests/zfs-tests/tests/functional/fault/cleanup.ksh
@@ -33,14 +33,4 @@ cleanup_devices $DISKS
 zed_stop
 zed_cleanup
 
-SDDEVICE=$(get_debug_device)
-
-# Offline disk and remove scsi_debug module
-if is_linux; then
-	if [ -n "$SDDEVICE" ]; then
-		remove_disk $SDDEVICE
-	fi
-	modprobe -r scsi_debug
-fi
-
 log_pass
diff --git a/tests/zfs-tests/tests/functional/fault/setup.ksh b/tests/zfs-tests/tests/functional/fault/setup.ksh
index 3d54d4f21754..3d3cbc9e568c 100755
--- a/tests/zfs-tests/tests/functional/fault/setup.ksh
+++ b/tests/zfs-tests/tests/functional/fault/setup.ksh
@@ -31,8 +31,4 @@ verify_runnable "global"
 zed_setup
 zed_start
 
-# Create a scsi_debug device to be used with auto-online (if using loop devices)
-# and auto-replace regardless of other devices
-load_scsi_debug $SDSIZE $SDHOSTS $SDTGTS $SDLUNS
-
 log_pass