diff --git a/cmd/zed/zed.d/all-syslog.sh b/cmd/zed/zed.d/all-syslog.sh
index cb9286500136..270b1bc67e5c 100755
--- a/cmd/zed/zed.d/all-syslog.sh
+++ b/cmd/zed/zed.d/all-syslog.sh
@@ -1,14 +1,50 @@
 #!/bin/sh
+#
+# Copyright (C) 2013-2014 Lawrence Livermore National Security, LLC.
+# Copyright (c) 2020 by Delphix. All rights reserved.
+#
+
 #
 # Log the zevent via syslog.
+#
 
 [ -f "${ZED_ZEDLET_DIR}/zed.rc" ] && . "${ZED_ZEDLET_DIR}/zed.rc"
 . "${ZED_ZEDLET_DIR}/zed-functions.sh"
 
 zed_exit_if_ignoring_this_event
 
-zed_log_msg "eid=${ZEVENT_EID}" "class=${ZEVENT_SUBCLASS}" \
-    "${ZEVENT_POOL_GUID:+"pool_guid=${ZEVENT_POOL_GUID}"}" \
-    "${ZEVENT_VDEV_PATH:+"vdev_path=${ZEVENT_VDEV_PATH}"}" \
-    "${ZEVENT_VDEV_STATE_STR:+"vdev_state=${ZEVENT_VDEV_STATE_STR}"}"
+# build a string of name=value pairs for this event
+msg="eid=${ZEVENT_EID} class=${ZEVENT_SUBCLASS}"
+
+if [ "${ZED_SYSLOG_DISPLAY_GUIDS}" = "1" ]; then
+    [ -n "${ZEVENT_POOL_GUID}" ] && msg="${msg} pool_guid=${ZEVENT_POOL_GUID}"
+    [ -n "${ZEVENT_VDEV_GUID}" ] && msg="${msg} vdev_guid=${ZEVENT_VDEV_GUID}"
+else
+    [ -n "${ZEVENT_POOL}" ] && msg="${msg} pool='${ZEVENT_POOL}'"
+    [ -n "${ZEVENT_VDEV_PATH}" ] && msg="${msg} vdev=$(basename "${ZEVENT_VDEV_PATH}")"
+fi
+
+# log pool state if state is anything other than 'ACTIVE'
+[ -n "${ZEVENT_POOL_STATE_STR}" ] && [ "$ZEVENT_POOL_STATE" -ne 0 ] && \
+    msg="${msg} pool_state=${ZEVENT_POOL_STATE_STR}"
+
+# Log the following payload nvpairs if they are present
+[ -n "${ZEVENT_VDEV_STATE_STR}" ]  && msg="${msg} vdev_state=${ZEVENT_VDEV_STATE_STR}"
+[ -n "${ZEVENT_CKSUM_ALGORITHM}" ] && msg="${msg} algorithm=${ZEVENT_CKSUM_ALGORITHM}"
+[ -n "${ZEVENT_ZIO_SIZE}" ]        && msg="${msg} size=${ZEVENT_ZIO_SIZE}"
+[ -n "${ZEVENT_ZIO_OFFSET}" ]      && msg="${msg} offset=${ZEVENT_ZIO_OFFSET}"
+[ -n "${ZEVENT_ZIO_PRIORITY}" ]    && msg="${msg} priority=${ZEVENT_ZIO_PRIORITY}"
+[ -n "${ZEVENT_ZIO_ERR}" ]         && msg="${msg} err=${ZEVENT_ZIO_ERR}"
+[ -n "${ZEVENT_ZIO_FLAGS}" ]       && msg="${msg} flags=$(printf '0x%x' "${ZEVENT_ZIO_FLAGS}")"
+
+# log delays that are >= 10 milisec
+[ -n "${ZEVENT_ZIO_DELAY}" ] && [ "$ZEVENT_ZIO_DELAY" -gt 10000000 ] && \
+    msg="${msg} delay=$((ZEVENT_ZIO_DELAY / 1000000))ms"
+
+# list the bookmark data together
+[ -n "${ZEVENT_ZIO_OBJSET}" ] && \
+    msg="${msg} bookmark=${ZEVENT_ZIO_OBJSET}:${ZEVENT_ZIO_OBJECT}:${ZEVENT_ZIO_LEVEL}:${ZEVENT_ZIO_BLKID}"
+
+zed_log_msg "${msg}"
+
 exit 0
diff --git a/cmd/zed/zed.d/zed.rc b/cmd/zed/zed.d/zed.rc
index 1b220d28db20..df560f921e60 100644
--- a/cmd/zed/zed.d/zed.rc
+++ b/cmd/zed/zed.d/zed.rc
@@ -1,122 +1,127 @@
 ##
 # zed.rc
 #
 # This file should be owned by root and permissioned 0600.
 ##
 
 ##
 # Absolute path to the debug output file.
 #
 #ZED_DEBUG_LOG="/tmp/zed.debug.log"
 
 ##
 # Email address of the zpool administrator for receipt of notifications;
 #   multiple addresses can be specified if they are delimited by whitespace.
 # Email will only be sent if ZED_EMAIL_ADDR is defined.
 # Disabled by default; uncomment to enable.
 #
 #ZED_EMAIL_ADDR="root"
 
 ##
 # Name or path of executable responsible for sending notifications via email;
 #   the mail program must be capable of reading a message body from stdin.
 # Email will only be sent if ZED_EMAIL_ADDR is defined.
 #
 #ZED_EMAIL_PROG="mail"
 
 ##
 # Command-line options for ZED_EMAIL_PROG.
 # The string @ADDRESS@ will be replaced with the recipient email address(es).
 # The string @SUBJECT@ will be replaced with the notification subject;
 #   this should be protected with quotes to prevent word-splitting.
 # Email will only be sent if ZED_EMAIL_ADDR is defined.
 #
 #ZED_EMAIL_OPTS="-s '@SUBJECT@' @ADDRESS@"
 
 ##
 # Default directory for zed lock files.
 #
 #ZED_LOCKDIR="/var/lock"
 
 ##
 # Minimum number of seconds between notifications for a similar event.
 #
 #ZED_NOTIFY_INTERVAL_SECS=3600
 
 ##
 # Notification verbosity.
 #   If set to 0, suppress notification if the pool is healthy.
 #   If set to 1, send notification regardless of pool health.
 #
 #ZED_NOTIFY_VERBOSE=0
 
 ##
 # Send notifications for 'ereport.fs.zfs.data' events.
 # Disabled by default, any non-empty value will enable the feature.
 #
 #ZED_NOTIFY_DATA=
 
 ##
 # Pushbullet access token.
 # This grants full access to your account -- protect it accordingly!
 #   <https://www.pushbullet.com/get-started>
 #   <https://www.pushbullet.com/account>
 # Disabled by default; uncomment to enable.
 #
 #ZED_PUSHBULLET_ACCESS_TOKEN=""
 
 ##
 # Pushbullet channel tag for push notification feeds that can be subscribed to.
 #   <https://www.pushbullet.com/my-channel>
 # If not defined, push notifications will instead be sent to all devices
 #   associated with the account specified by the access token.
 # Disabled by default; uncomment to enable.
 #
 #ZED_PUSHBULLET_CHANNEL_TAG=""
 
 ##
 # Slack Webhook URL.
 # This allows posting to the given channel and includes an access token.
 #   <https://api.slack.com/incoming-webhooks>
 # Disabled by default; uncomment to enable.
 #
 #ZED_SLACK_WEBHOOK_URL=""
 
 ##
 # Default directory for zed state files.
 #
 #ZED_RUNDIR="/var/run"
 
 ##
 # Turn on/off enclosure LEDs when drives get DEGRADED/FAULTED.  This works for
 # device mapper and multipath devices as well.  Your enclosure must be
 # supported by the Linux SES driver for this to work.
 #
 ZED_USE_ENCLOSURE_LEDS=1
 
 ##
 # Run a scrub after every resilver
 # Disabled by default, 1 to enable and 0 to disable.
 #ZED_SCRUB_AFTER_RESILVER=0
 
 ##
 # The syslog priority (e.g., specified as a "facility.level" pair).
 #
 #ZED_SYSLOG_PRIORITY="daemon.notice"
 
 ##
 # The syslog tag for marking zed events.
 #
 #ZED_SYSLOG_TAG="zed"
 
 ##
 # Which set of event subclasses to log
 # By default, events from all subclasses are logged.
 # If ZED_SYSLOG_SUBCLASS_INCLUDE is set, only subclasses
 # matching the pattern are logged. Use the pipe symbol (|)
 # or shell wildcards (*, ?) to match multiple subclasses.
 # Otherwise, if ZED_SYSLOG_SUBCLASS_EXCLUDE is set, the
 # matching subclasses are excluded from logging.
 #ZED_SYSLOG_SUBCLASS_INCLUDE="checksum|scrub_*|vdev.*"
-#ZED_SYSLOG_SUBCLASS_EXCLUDE="statechange|config_*|history_event"
+ZED_SYSLOG_SUBCLASS_EXCLUDE="history_event"
+
+##
+# Use GUIDs instead of names when logging pool and vdevs
+# Disabled by default, 1 to enable and 0 to disable.
+#ZED_SYSLOG_DISPLAY_GUIDS=1
 
diff --git a/tests/zfs-tests/tests/functional/events/events_001_pos.ksh b/tests/zfs-tests/tests/functional/events/events_001_pos.ksh
index 5121f66b78b0..189cf435e88e 100755
--- a/tests/zfs-tests/tests/functional/events/events_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/events/events_001_pos.ksh
@@ -1,153 +1,153 @@
 #!/bin/ksh -p
 #
 # CDDL HEADER START
 #
 # The contents of this file are subject to the terms of the
 # Common Development and Distribution License (the "License").
 # You may not use this file except in compliance with the License.
 #
 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 # or http://www.opensolaris.org/os/licensing.
 # See the License for the specific language governing permissions
 # and limitations under the License.
 #
 # When distributing Covered Code, include this CDDL HEADER in each
 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 # If applicable, add the following below this CDDL HEADER, with the
 # fields enclosed by brackets "[]" replaced with your own identifying
 # information: Portions Copyright [yyyy] [name of copyright owner]
 #
 # CDDL HEADER END
 #
 
 #
 # Copyright (c) 2017 by Lawrence Livermore National Security, LLC.
 # Use is subject to license terms.
 #
 
 # DESCRIPTION:
 # Verify zpool events command logs events.
 #
 # STRATEGY:
 # 1. Execute zpool sub-commands on a pool.
 # 2. Verify the expected events are logged in 'zpool events'.
 # 3. Verify the expected events are logged by the ZED.
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/events/events_common.kshlib
 
 verify_runnable "both"
 
 function cleanup
 {
 	if poolexists $MPOOL; then
 		destroy_pool $MPOOL
 	fi
 
 	for file in $VDEV1 $VDEV2 $VDEV3 $VDEV4; do
 		[[ -f $file ]] && rm -f $file
 	done
 
 	log_must zed_stop
 }
 
 log_assert "Verify zpool sub-commands generate expected events"
 log_onexit cleanup
 
 log_must truncate -s $MINVDEVSIZE $VDEV1 $VDEV2 $VDEV3 $VDEV4
 
 log_must zpool events -c
 log_must zed_start
 
 # Create a mirrored pool with two devices.
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.pool_create" \
     -e "sysevent.fs.zfs.history_event" \
     -e "sysevent.fs.zfs.config_sync" \
     "zpool create $MPOOL mirror $VDEV1 $VDEV2"
 
 # Set a pool property.
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.history_event" \
     "zpool set comment=string $MPOOL"
 
 # Add a cache device then remove it.
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.config_sync" \
     -e "sysevent.fs.zfs.vdev_add" \
     "zpool add -f $MPOOL spare $VDEV3"
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.vdev_remove_aux" \
     "zpool remove $MPOOL $VDEV3"
 
 # Add a log device then remove it.
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.config_sync" \
     -e "sysevent.fs.zfs.vdev_add" \
     "zpool add -f $MPOOL log $VDEV3"
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.vdev_remove_dev" \
     "zpool remove $MPOOL $VDEV3"
 
 # Offline then online a device.
 run_and_verify -p "$MPOOL"\
     -e "resource.fs.zfs.statechange" \
     -e "sysevent.fs.zfs.config_sync" \
     "zpool offline $MPOOL $VDEV1"
-run_and_verify -p "$MPOOL" -d 10 \
+run_and_verify -p "$MPOOL" \
     -e "resource.fs.zfs.statechange" \
     -e "sysevent.fs.zfs.vdev_online" \
+    -e "sysevent.fs.zfs.config_sync" \
     -e "sysevent.fs.zfs.resilver_start" \
-    -e "sysevent.fs.zfs.resilver_finish" \
     -e "sysevent.fs.zfs.history_event" \
-    -e "sysevent.fs.zfs.config_sync" \
+    -e "sysevent.fs.zfs.resilver_finish" \
     "zpool online $MPOOL $VDEV1"
 
 # Attach then detach a device from the mirror.
-run_and_verify -p "$MPOOL" -d 10 \
+run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.vdev_attach" \
     -e "sysevent.fs.zfs.resilver_start" \
-    -e "sysevent.fs.zfs.resilver_finish" \
-    -e "sysevent.fs.zfs.history_event" \
     -e "sysevent.fs.zfs.config_sync" \
+    -e "sysevent.fs.zfs.history_event" \
+    -e "sysevent.fs.zfs.resilver_finish" \
     "zpool attach $MPOOL $VDEV1 $VDEV4"
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.vdev_remove" \
     -e "sysevent.fs.zfs.config_sync" \
     "zpool detach $MPOOL $VDEV4"
 
 # Replace a device
-run_and_verify -p "$MPOOL" -d 10 \
+run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.vdev_attach" \
     -e "sysevent.fs.zfs.resilver_start" \
+    -e "sysevent.fs.zfs.config_sync" \
+    -e "sysevent.fs.zfs.history_event" \
     -e "sysevent.fs.zfs.resilver_finish" \
     -e "sysevent.fs.zfs.vdev_remove" \
-    -e "sysevent.fs.zfs.history_event" \
-    -e "sysevent.fs.zfs.config_sync" \
     "zpool replace -f $MPOOL $VDEV1 $VDEV4"
 
 # Scrub a pool.
-run_and_verify -p "$MPOOL" -d 10 \
+run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.scrub_start" \
-    -e "sysevent.fs.zfs.scrub_finish" \
     -e "sysevent.fs.zfs.history_event" \
+    -e "sysevent.fs.zfs.scrub_finish" \
     "zpool scrub $MPOOL"
 
 # Export then import a pool
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.pool_export" \
     -e "sysevent.fs.zfs.config_sync" \
     "zpool export $MPOOL"
 run_and_verify -p "$MPOOL" \
-    -e "sysevent.fs.zfs.pool_import" \
-    -e "sysevent.fs.zfs.history_event" \
     -e "sysevent.fs.zfs.config_sync" \
+    -e "sysevent.fs.zfs.history_event" \
+    -e "sysevent.fs.zfs.pool_import" \
     "zpool import -d $TEST_BASE_DIR $MPOOL"
 
 # Destroy the pool
 run_and_verify -p "$MPOOL" \
     -e "sysevent.fs.zfs.pool_destroy" \
     -e "sysevent.fs.zfs.config_sync" \
     "zpool destroy $MPOOL"
 
 log_pass "Verify zpool sub-commands generate expected events"
diff --git a/tests/zfs-tests/tests/functional/events/events_002_pos.ksh b/tests/zfs-tests/tests/functional/events/events_002_pos.ksh
index 76ad6237fc23..7a78d93a8438 100755
--- a/tests/zfs-tests/tests/functional/events/events_002_pos.ksh
+++ b/tests/zfs-tests/tests/functional/events/events_002_pos.ksh
@@ -1,103 +1,103 @@
 #!/bin/ksh -p
 #
 # CDDL HEADER START
 #
 # The contents of this file are subject to the terms of the
 # Common Development and Distribution License (the "License").
 # You may not use this file except in compliance with the License.
 #
 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 # or http://www.opensolaris.org/os/licensing.
 # See the License for the specific language governing permissions
 # and limitations under the License.
 #
 # When distributing Covered Code, include this CDDL HEADER in each
 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 # If applicable, add the following below this CDDL HEADER, with the
 # fields enclosed by brackets "[]" replaced with your own identifying
 # information: Portions Copyright [yyyy] [name of copyright owner]
 #
 # CDDL HEADER END
 #
 
 #
 # Copyright (c) 2017 by Lawrence Livermore National Security, LLC.
 # Use is subject to license terms.
 #
 
 # DESCRIPTION:
 # Verify ZED handles missed events from a pool when starting.
 #
 # STRATEGY:
 # 1. Clear the events and create a pool to generate some events.
 # 2. Start the ZED and verify it handles missed events.
 # 3. Stop the ZED
 # 4. Generate additional events.
 # 5. Start the ZED and verify it only handles the new missed events.
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/events/events_common.kshlib
 
 verify_runnable "both"
 
 function cleanup
 {
 	if poolexists $MPOOL; then
 		destroy_pool $MPOOL
 	fi
 
 	for file in $VDEV1 $VDEV2; do
 		[[ -f $file ]] && rm -f $file
 	done
 
 	log_must rm -f $TMP_EVENTS_ZED $TMP_EVENTS_ZED
 	log_must zed_stop
 }
 
 log_assert "Verify ZED handles missed events on when starting"
 log_onexit cleanup
 
 log_must truncate -s $MINVDEVSIZE $VDEV1 $VDEV2
 
 # 1. Create a pool and generate some events.
 log_must truncate -s 0 $ZED_DEBUG_LOG
 log_must zpool events -c
 log_must zpool create $MPOOL mirror $VDEV1 $VDEV2
 
 # 2. Start the ZED and verify it handles missed events.
 log_must zed_start
 log_must file_wait $ZED_DEBUG_LOG
 log_must cp $ZED_DEBUG_LOG $TMP_EVENTS_ZED
 
 awk -v event="sysevent.fs.zfs.pool_create" \
     'BEGIN{FS="\n"; RS=""} $0 ~ event { print $0 }' \
     $TMP_EVENTS_ZED >$TMP_EVENT_ZED
 log_must grep -q "^ZEVENT_POOL=$MPOOL" $TMP_EVENT_ZED
 
 # 3. Stop the ZED
 zed_stop
 log_must truncate -s 0 $ZED_DEBUG_LOG
 
 # 4. Generate additional events.
 log_must zpool offline $MPOOL $VDEV1
 log_must zpool online $MPOOL $VDEV1
 log_must zpool wait -t resilver $MPOOL
 
 log_must zpool scrub $MPOOL
 
 # Wait for the scrub to wrap, or is_healthy will be wrong.
 while ! is_pool_scrubbed $MPOOL; do
 	sleep 1
 done
 
 # 5. Start the ZED and verify it only handled the new missed events.
 log_must zed_start
-log_must file_wait $ZED_DEBUG_LOG 15
+log_must file_wait $ZED_DEBUG_LOG 35
 log_must cp $ZED_DEBUG_LOG $TMP_EVENTS_ZED
 
 log_mustnot grep -q "sysevent.fs.zfs.pool_create" $TMP_EVENTS_ZED
 log_must grep -q "sysevent.fs.zfs.vdev_online" $TMP_EVENTS_ZED
 log_must grep -q "sysevent.fs.zfs.resilver_start" $TMP_EVENTS_ZED
 log_must grep -q "sysevent.fs.zfs.resilver_finish" $TMP_EVENTS_ZED
 
 log_pass "Verify ZED handles missed events on when starting"
diff --git a/tests/zfs-tests/tests/functional/events/events_common.kshlib b/tests/zfs-tests/tests/functional/events/events_common.kshlib
index 26afc109174f..5f4c629dca47 100644
--- a/tests/zfs-tests/tests/functional/events/events_common.kshlib
+++ b/tests/zfs-tests/tests/functional/events/events_common.kshlib
@@ -1,130 +1,161 @@
 #
 # CDDL HEADER START
 #
 # The contents of this file are subject to the terms of the
 # Common Development and Distribution License (the "License").
 # You may not use this file except in compliance with the License.
 #
 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 # or http://www.opensolaris.org/os/licensing.
 # See the License for the specific language governing permissions
 # and limitations under the License.
 #
 # When distributing Covered Code, include this CDDL HEADER in each
 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 # If applicable, add the following below this CDDL HEADER, with the
 # fields enclosed by brackets "[]" replaced with your own identifying
 # information: Portions Copyright [yyyy] [name of copyright owner]
 #
 # CDDL HEADER END
 #
 
 #
 # Copyright (c) 2017 by Lawrence Livermore National Security, LLC.
 # Use is subject to license terms.
 #
+# Copyright (c) 2020 by Delphix. All rights reserved.
+#
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/events/events.cfg
 
+#
+# wait for 'event' to show up in the log 'file'
+function file_wait_event # file event timeout
+{
+	file=$1
+	event=$2
+	timeout=${3:-120}
+
+	SECONDS=0
+
+	until grep -q "^ZEVENT_CLASS=$event" $ZED_DEBUG_LOG ; do
+		if [[ $SECONDS -gt $timeout ]]; then
+			echo file_wait_event exceeded $SECONDS seconds
+			return 1
+		fi
+
+		sleep 1
+	done
+
+	return 0;
+}
+
 #
 # Wait for up to 'timeout' seconds for the 'file' to settle, i.e.
 # not be updated for a period of 'delay' seconds.
 #
 function file_wait # file delay timeout
 {
 	file=$1
 	delay=${2:-3}
 	timeout=${3:-120}
 
 	SECONDS=0
 
 	while [ $(( $(date +%s) - $(stat -c %Y $file) )) -lt $delay ]; do
 		if [[ $SECONDS -gt $timeout ]]; then
+			echo file_wait exceeded $SECONDS seconds
 			return 1
 		fi
 
 		sleep 1
 	done
 
 	return 0;
 }
 
 function run_and_verify
 {
-	typeset delay event pool zedlog
+	typeset event pool
 	set -A events
 
-	while getopts "d:e:p:z:" opt; do
+	while getopts "e:p:" opt; do
 		case $opt in
-		d)
-			delay=$OPTARG
-			;;
 		e)
-			events[${#events[*]}+1]=$OPTARG
+			events+=("$OPTARG")
 			;;
 		p)
 			pool=$OPTARG
 			;;
-		z)
-			zedlog=$OPTARG
-			;;
 		esac
 	done
 	shift $(($OPTIND - 1))
 
 	pool=${pool:-$TESTPOOL}
-	delay=${delay:-3}
-	zedlog=${zedlog:-$ZED_DEBUG_LOG}
 	fullcmd="$1"
 	cmd=$(echo $fullcmd | awk '{print $1}')
 
 	# If we aren't running zpool or zfs, something is wrong
 	[[ $cmd == "zpool" || $cmd == "zfs" ]] || \
 	    log_fail "run_and_verify called with \"$cmd ($fullcmd)\""
 
 	log_note "Checking events for command: '$fullcmd'"
 
 	# Remove any previous events from the logs.
 	log_must zpool events -c
-	log_must truncate -s 0 $zedlog
+	log_must truncate -s 0 $ZED_DEBUG_LOG
 
 	# Run the command as provided.
 	log_must eval "$fullcmd"
 
 	# Collect the new events and verify there are some.
 	log_must zpool sync -f
-	log_must file_wait $zedlog $delay
-	log_must cp $zedlog $TMP_EVENTS_ZED
 	log_must eval "zpool events >$TMP_EVENTS 2>/dev/null"
 	log_must eval "zpool events -v > $TMP_EVENTS_FULL 2>/dev/null"
 
 	log_must test -s $TMP_EVENTS
 	log_must test -s $TMP_EVENTS_FULL
-	log_must test -s $TMP_EVENTS_ZED
+
+	# If the only event is history then we don't observe zed debug log
+	if [[ "${events[0]}" != "sysevent.fs.zfs.history_event" ]]; then
+		# wait for the last event to show up in the debug log
+		log_must file_wait_event $ZED_DEBUG_LOG ${events[-1]}
+
+		log_must cp $ZED_DEBUG_LOG $TMP_EVENTS_ZED
+		log_must test -s $TMP_EVENTS_ZED
+
+		log_note "Events logged:"
+		grep "^ZEVENT_CLASS" $TMP_EVENTS_ZED
+	fi
 
 	log_note "Events generated:"
 	cat $TMP_EVENTS
 
 	# Verify all the expected events appear in the log.
 	for event in ${events[*]}; do
 
 		# Verify the event is in in the short output.
 		log_must grep -q "$event" $TMP_EVENTS
 
 		# Verify the event is in the verbose output with pool name.
 		awk -v event="$event" \
 		    'BEGIN{FS="\n"; RS=""} $0 ~ event { print $0 }' \
 		    $TMP_EVENTS_FULL >$TMP_EVENT_FULL
 		log_must grep -q "pool = \"$pool\"" $TMP_EVENT_FULL
 
+		# all-debug.sh filters history events (seen in ZED_DEBUG_LOG)
+		if [[ "$event" == "sysevent.fs.zfs.history_event" ]]; then
+			continue
+		fi
+
 		# Verify the event was received by the ZED and logged.
 		awk -v event="$event" \
 		    'BEGIN{FS="\n"; RS=""} $0 ~ event { print $0 }' \
 		    $TMP_EVENTS_ZED >$TMP_EVENT_ZED
 		log_must grep -q "^ZEVENT_POOL=$pool" $TMP_EVENT_ZED
 	done
 
 	rm -f $TMP_EVENTS $TMP_EVENTS_FULL $TMP_EVENT_FULL \
 	    $TMP_EVENTS_ZED $TMP_EVENT_ZED
 }