diff --git a/tests/zfs-tests/tests/functional/online_offline/online_offline_001_pos.ksh b/tests/zfs-tests/tests/functional/online_offline/online_offline_001_pos.ksh
index c7b7ca789344..aacec48df956 100755
--- a/tests/zfs-tests/tests/functional/online_offline/online_offline_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/online_offline/online_offline_001_pos.ksh
@@ -1,91 +1,92 @@
 #!/bin/ksh -p
 # SPDX-License-Identifier: CDDL-1.0
 #
 # 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 https://opensource.org/licenses/CDDL-1.0.
 # 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 2009 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
 
 #
 # Copyright (c) 2013, 2016 by Delphix. All rights reserved.
 #
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/online_offline/online_offline.cfg
 
 #
 # DESCRIPTION:
 # Turning a disk offline and back online during I/O completes.
 #
 # STRATEGY:
 # 1. Create a mirror and start some random I/O
 # 2. For each disk in the mirror, set it offline and online
 # 3. Verify the integrity of the file system and the resilvering.
 #
 
 verify_runnable "global"
 log_onexit cleanup
 
 DISKLIST=$(get_disklist $TESTPOOL)
 
 function cleanup
 {
 	kill $killpid >/dev/null 2>&1
 
 	#
 	# Ensure we don't leave disks in the offline state
 	#
 	for disk in $DISKLIST; do
 		log_must zpool online $TESTPOOL $disk
 		log_must check_state $TESTPOOL $disk "online"
 	done
+	sleep 1 # Delay for resilver to start
 	log_must zpool wait -t resilver $TESTPOOL
 
 	[[ -e $TESTDIR ]] && log_must rm -rf $TESTDIR/*
 }
 
 log_assert "Turning a disk offline and back online during I/O completes."
 
 file_trunc -f $((64 * 1024 * 1024)) -b 8192 -c 0 -r $TESTDIR/$TESTFILE1 &
 typeset killpid="$! "
 
 for disk in $DISKLIST; do
 	for i in 'do_offline' 'do_offline_while_already_offline'; do
 		log_must zpool offline $TESTPOOL $disk
 		log_must check_state $TESTPOOL $disk "offline"
 	done
 
 	log_must zpool online $TESTPOOL $disk
 	log_must check_state $TESTPOOL $disk "online"
-
+	sleep 1 # Delay for resilver to start
 	log_must zpool wait -t resilver $TESTPOOL
 done
 
 log_must kill $killpid
 sync_all_pools
 log_must sync
 
 typeset dir=$(get_device_dir $DISKS)
 verify_filesys "$TESTPOOL" "$TESTPOOL/$TESTFS" "$dir"
 
 log_pass
diff --git a/tests/zfs-tests/tests/functional/online_offline/online_offline_002_neg.ksh b/tests/zfs-tests/tests/functional/online_offline/online_offline_002_neg.ksh
index 5da90b4d6454..0155303b8202 100755
--- a/tests/zfs-tests/tests/functional/online_offline/online_offline_002_neg.ksh
+++ b/tests/zfs-tests/tests/functional/online_offline/online_offline_002_neg.ksh
@@ -1,137 +1,140 @@
 #!/bin/ksh -p
 # SPDX-License-Identifier: CDDL-1.0
 #
 # 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 https://opensource.org/licenses/CDDL-1.0.
 # 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 2009 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
 
 #
 # Copyright (c) 2013, 2016 by Delphix. All rights reserved.
 #
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/online_offline/online_offline.cfg
 
 #
 # DESCRIPTION:
 # Turning disks in a pool offline should fail when there is no longer
 # sufficient redundancy.
 #
 # STRATEGY:
 # 1. Start some random I/O on the mirror or raidz.
 # 2. Verify that we can offline as many disks as the redundancy level
 # will support, but not more.
 # 3. Verify the integrity of the file system and the resilvering.
 #
 
 verify_runnable "global"
 
 DISKLIST=$(get_disklist $TESTPOOL)
 
 function cleanup
 {
 	kill $killpid >/dev/null 2>&1
 
 	#
 	# Ensure we don't leave disks in the offline state
 	#
 	for disk in $DISKLIST; do
 		log_must zpool online $TESTPOOL $disk
 		log_must check_state $TESTPOOL $disk "online"
 	done
+	sleep 1 # Delay for resilver to start
 	log_must zpool wait -t resilver $TESTPOOL
 
 	[[ -e $TESTDIR ]] && log_must rm -rf $TESTDIR/*
 }
 
 log_assert "Turning both disks offline should fail."
 
 log_onexit cleanup
 
 file_trunc -f $((64 * 1024 * 1024)) -b 8192 -c 0 -r $TESTDIR/$TESTFILE1 &
 typeset killpid="$! "
 
 disks=($DISKLIST)
 
 #
 # The setup script will give us either a mirror or a raidz. The former can have
 # all but one vdev offlined, whereas with raidz there can be only one.
 #
 pooltype='mirror'
 zpool list -v $TESTPOOL | grep raidz >/dev/null 2>&1 && pooltype='raidz'
 
 typeset -i i=0
 while [[ $i -lt ${#disks[*]} ]]; do
 	typeset -i j=0
 	if [[ $pooltype = 'mirror' ]]; then
 		# Hold one disk online, verify the others can be offlined.
 		log_must zpool online $TESTPOOL ${disks[$i]}
 		check_state $TESTPOOL ${disks[$i]} "online" || \
 		    log_fail "Failed to set ${disks[$i]} online"
+		sleep 1 # Delay for resilver to start
 		log_must zpool wait -t resilver $TESTPOOL
 		log_must zpool clear $TESTPOOL
 		while [[ $j -lt ${#disks[*]} ]]; do
 			if [[ $j -eq $i ]]; then
 				((j++))
 				continue
 			fi
 			log_must zpool offline $TESTPOOL ${disks[$j]}
 			check_state $TESTPOOL ${disks[$j]} "offline" || \
 			    log_fail "Failed to set ${disks[$j]} offline"
 			((j++))
 		done
 	elif [[ $pooltype = 'raidz' ]]; then
 		# Hold one disk offline, verify the others can't be offlined.
 		log_must zpool offline $TESTPOOL ${disks[$i]}
 		check_state $TESTPOOL ${disks[$i]} "offline" || \
 		    log_fail "Failed to set ${disks[$i]} offline"
 		while [[ $j -lt ${#disks[*]} ]]; do
 			if [[ $j -eq $i ]]; then
 				((j++))
 				continue
 			fi
 			log_mustnot zpool offline $TESTPOOL ${disks[$j]}
 			check_state $TESTPOOL ${disks[$j]} "online" || \
 			    log_fail "Failed to set ${disks[$j]} online"
 			check_state $TESTPOOL ${disks[$i]} "offline" || \
 			    log_fail "Failed to set ${disks[$i]} offline"
 			((j++))
 		done
 		log_must zpool online $TESTPOOL ${disks[$i]}
 		check_state $TESTPOOL ${disks[$i]} "online" || \
 		    log_fail "Failed to set ${disks[$i]} online"
+		sleep 1 # Delay for resilver to start
 		log_must zpool wait -t resilver $TESTPOOL
 		log_must zpool clear $TESTPOOL
 	fi
 	((i++))
 done
 
 log_must kill $killpid
 sync_all_pools
 log_must sync
 
 typeset dir=$(get_device_dir $DISKS)
 verify_filesys "$TESTPOOL" "$TESTPOOL/$TESTFS" "$dir"
 
 log_pass