diff --git a/tests/zfs-tests/tests/functional/alloc_class/alloc_class.kshlib b/tests/zfs-tests/tests/functional/alloc_class/alloc_class.kshlib
index e204f43b3b..795e71b26b 100644
--- a/tests/zfs-tests/tests/functional/alloc_class/alloc_class.kshlib
+++ b/tests/zfs-tests/tests/functional/alloc_class/alloc_class.kshlib
@@ -55,7 +55,7 @@ function display_status
 	((ret |= $?))
 
 	typeset mntpnt=$(get_prop mountpoint $pool)
-	dd if=/dev/random of=$mntpnt/testfile.$$ &
+	dd if=/dev/urandom of=$mntpnt/testfile.$$ &
 	typeset pid=$!
 
 	zpool iostat -v 1 3 > /dev/null
diff --git a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_rlimit_fsize.ksh b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_rlimit_fsize.ksh
index a8a64e5249..3632fc9a4d 100755
--- a/tests/zfs-tests/tests/functional/block_cloning/block_cloning_rlimit_fsize.ksh
+++ b/tests/zfs-tests/tests/functional/block_cloning/block_cloning_rlimit_fsize.ksh
@@ -54,7 +54,7 @@ log_must truncate -s 1G $VDEV
 
 log_must zpool create -o feature@block_cloning=enabled $TESTPOOL $VDEV
 
-log_must dd if=/dev/random of=/$TESTPOOL/file1 bs=1 count=1000
+log_must dd if=/dev/urandom of=/$TESTPOOL/file1 bs=1 count=1000
 
 ulimit -f 2
 log_must clonefile -f /$TESTPOOL/file1 /$TESTPOOL/file2 0 0 all
diff --git a/tests/zfs-tests/tests/functional/fault/suspend_resume_single.ksh b/tests/zfs-tests/tests/functional/fault/suspend_resume_single.ksh
index 041dadb1ea..05f3ac7084 100755
--- a/tests/zfs-tests/tests/functional/fault/suspend_resume_single.ksh
+++ b/tests/zfs-tests/tests/functional/fault/suspend_resume_single.ksh
@@ -42,7 +42,7 @@ log_onexit cleanup
 log_assert "ensure single-disk pool resumes properly after suspend and clear"
 
 # create a file, and take a checksum, so we can compare later
-log_must dd if=/dev/random of=$DATAFILE bs=128K count=1
+log_must dd if=/dev/urandom of=$DATAFILE bs=128K count=1
 typeset sum1=$(cat $DATAFILE | md5sum)
 
 # make a debug device that we can "unplug"