diff --git a/tests/zfs-tests/tests/functional/cli_root/zdb/zdb_004_pos.ksh b/tests/zfs-tests/tests/functional/cli_root/zdb/zdb_004_pos.ksh
index 2adaf8fac..b20eee672 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zdb/zdb_004_pos.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zdb/zdb_004_pos.ksh
@@ -40,12 +40,12 @@ function cleanup
 	for DISK in $DISKS; do
 		zpool labelclear -f $DEV_RDSKDIR/$DISK
 	done
-	if is_freebsd ; then
+	if is_freebsd; then
 		log_must sysctl kern.geom.debugflags=$saved_debugflags
 	fi
 }
 
-if is_freebsd ; then
+if is_freebsd; then
 	# FreeBSD won't allow writing to an in-use device without this set
 	saved_debugflags=$(sysctl -n kern.geom.debugflags)
 	log_must sysctl kern.geom.debugflags=16
@@ -54,32 +54,21 @@ fi
 verify_runnable "global"
 verify_disk_count "$DISKS" 2
 set -A DISK $DISKS
-if is_freebsd ; then
-	WHOLE_DISK=/dev/${DISK[0]}
-else
-	WHOLE_DISK=${DISK[0]}
-fi
 
 default_mirror_setup_noexit $DISKS
 DEVS=$(get_pool_devices ${TESTPOOL} ${DEV_RDSKDIR})
 [[ -n $DEVS ]] && set -A DISK $DEVS
 
-log_must zpool offline $TESTPOOL ${WHOLE_DISK}
+log_must zpool offline $TESTPOOL ${DISK[0]}
 log_must dd if=/dev/urandom of=$TESTDIR/testfile bs=1K count=2
 log_must zpool export $TESTPOOL
 
 log_must dd if=$DEV_RDSKDIR/${DISK[0]} of=$DEV_RDSKDIR/${DISK[1]} bs=1K count=256 conv=notrunc
 
-if is_freebsd; then
-	DISK1="/dev/${DISK[1]}"
-else
-	DISK1="${DISK[1]}"
-fi
-
-ubs=$(zdb -lu ${DISK1} | grep -e LABEL -e Uberblock -e 'labels = ')
+ubs=$(zdb -lu ${DISK[1]} | grep -e LABEL -e Uberblock -e 'labels = ')
 log_note "vdev 1: ubs $ubs"
 
-ub_dump_counts=$(zdb -lu ${DISK1} | \
+ub_dump_counts=$(zdb -lu ${DISK[1]} | \
 	awk '	/LABEL/	{label=$NF; blocks[label]=0};
 		/Uberblock/ {blocks[label]++};
 		END {print blocks[0],blocks[1],blocks[2],blocks[3]}')