diff --git a/cmd/zdb/zdb.c b/cmd/zdb/zdb.c
index 1ca97d5c1..45eb9c783 100644
--- a/cmd/zdb/zdb.c
+++ b/cmd/zdb/zdb.c
@@ -2545,12 +2545,14 @@ snprintf_blkptr_compact(char *blkbuf, size_t buflen, const blkptr_t *bp,
 
 	blkbuf[0] = '\0';
 
-	for (i = 0; i < ndvas; i++)
+	for (i = 0; i < ndvas; i++) {
 		(void) snprintf(blkbuf + strlen(blkbuf),
-		    buflen - strlen(blkbuf), "%llu:%llx:%llx ",
+		    buflen - strlen(blkbuf), "%llu:%llx:%llx%s ",
 		    (u_longlong_t)DVA_GET_VDEV(&dva[i]),
 		    (u_longlong_t)DVA_GET_OFFSET(&dva[i]),
-		    (u_longlong_t)DVA_GET_ASIZE(&dva[i]));
+		    (u_longlong_t)DVA_GET_ASIZE(&dva[i]),
+		    (DVA_GET_GANG(&dva[i]) ? "G" : ""));
+	}
 
 	if (BP_IS_HOLE(bp)) {
 		(void) snprintf(blkbuf + strlen(blkbuf),
@@ -8981,7 +8983,7 @@ zdb_read_block(char *thing, spa_t *spa)
 
 	DVA_SET_VDEV(&dva[0], vd->vdev_id);
 	DVA_SET_OFFSET(&dva[0], offset);
-	DVA_SET_GANG(&dva[0], !!(flags & ZDB_FLAG_GBH));
+	DVA_SET_GANG(&dva[0], 0);
 	DVA_SET_ASIZE(&dva[0], vdev_psize_to_asize(vd, psize));
 
 	BP_SET_BIRTH(bp, TXG_INITIAL, TXG_INITIAL);
@@ -8996,7 +8998,7 @@ zdb_read_block(char *thing, spa_t *spa)
 	BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
 
 	spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
-	zio = zio_root(spa, NULL, NULL, 0);
+	zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL);
 
 	if (vd == vd->vdev_top) {
 		/*
diff --git a/include/sys/dbuf.h b/include/sys/dbuf.h
index 2e9b7edf8..285e02484 100644
--- a/include/sys/dbuf.h
+++ b/include/sys/dbuf.h
@@ -174,6 +174,7 @@ typedef struct dbuf_dirty_record {
 			arc_buf_t *dr_data;
 			override_states_t dr_override_state;
 			uint8_t dr_copies;
+			uint8_t dr_gang_copies;
 			boolean_t dr_nopwrite;
 			boolean_t dr_brtwrite;
 			boolean_t dr_diowrite;
diff --git a/include/sys/zio.h b/include/sys/zio.h
index af47d6f87..78adca4d7 100644
--- a/include/sys/zio.h
+++ b/include/sys/zio.h
@@ -350,6 +350,7 @@ typedef struct zio_prop {
 	uint8_t			zp_complevel;
 	uint8_t			zp_level;
 	uint8_t			zp_copies;
+	uint8_t			zp_gang_copies;
 	dmu_object_type_t	zp_type;
 	boolean_t		zp_dedup;
 	boolean_t		zp_dedup_verify;
@@ -575,7 +576,7 @@ extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
     zio_priority_t priority, zio_flag_t flags, zbookmark_phys_t *zb);
 
 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
-    boolean_t nopwrite, boolean_t brtwrite);
+    int gang_copies, boolean_t nopwrite, boolean_t brtwrite);
 
 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
 
diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index e97d588b4..d07a5f076 100644
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -6887,6 +6887,8 @@ arc_write(zio_t *pio, spa_t *spa, uint64_t txg,
 			localprop.zp_nopwrite = B_FALSE;
 			localprop.zp_copies =
 			    MIN(localprop.zp_copies, SPA_DVAS_PER_BP - 1);
+			localprop.zp_gang_copies =
+			    MIN(localprop.zp_gang_copies, SPA_DVAS_PER_BP - 1);
 		}
 		zio_flags |= ZIO_FLAG_RAW;
 	} else if (ARC_BUF_COMPRESSED(buf)) {
diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
index 01f92411b..0a243a242 100644
--- a/module/zfs/dbuf.c
+++ b/module/zfs/dbuf.c
@@ -5352,8 +5352,8 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx)
 		mutex_enter(&db->db_mtx);
 		dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
 		zio_write_override(dr->dr_zio, &dr->dt.dl.dr_overridden_by,
-		    dr->dt.dl.dr_copies, dr->dt.dl.dr_nopwrite,
-		    dr->dt.dl.dr_brtwrite);
+		    dr->dt.dl.dr_copies, dr->dt.dl.dr_gang_copies,
+		    dr->dt.dl.dr_nopwrite, dr->dt.dl.dr_brtwrite);
 		mutex_exit(&db->db_mtx);
 	} else if (data == NULL) {
 		ASSERT(zp.zp_checksum == ZIO_CHECKSUM_OFF ||
diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c
index bddb90f29..2b52ae139 100644
--- a/module/zfs/dmu.c
+++ b/module/zfs/dmu.c
@@ -1916,6 +1916,7 @@ dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
 		dr->dt.dl.dr_overridden_by = *zio->io_bp;
 		dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
 		dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
+		dr->dt.dl.dr_gang_copies = zio->io_prop.zp_gang_copies;
 
 		/*
 		 * Old style holes are filled with all zeros, whereas
@@ -2322,6 +2323,7 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 	boolean_t dedup_verify = os->os_dedup_verify;
 	boolean_t encrypt = B_FALSE;
 	int copies = os->os_copies;
+	int gang_copies = os->os_copies;
 
 	/*
 	 * We maintain different write policies for each of the following
@@ -2354,15 +2356,24 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 		switch (os->os_redundant_metadata) {
 		case ZFS_REDUNDANT_METADATA_ALL:
 			copies++;
+			gang_copies++;
 			break;
 		case ZFS_REDUNDANT_METADATA_MOST:
 			if (level >= zfs_redundant_metadata_most_ditto_level ||
 			    DMU_OT_IS_METADATA(type) || (wp & WP_SPILL))
 				copies++;
+			if (level + 1 >=
+			    zfs_redundant_metadata_most_ditto_level ||
+			    DMU_OT_IS_METADATA(type) || (wp & WP_SPILL))
+				gang_copies++;
 			break;
 		case ZFS_REDUNDANT_METADATA_SOME:
-			if (DMU_OT_IS_CRITICAL(type))
+			if (DMU_OT_IS_CRITICAL(type)) {
 				copies++;
+				gang_copies++;
+			} else if (DMU_OT_IS_METADATA(type)) {
+				gang_copies++;
+			}
 			break;
 		case ZFS_REDUNDANT_METADATA_NONE:
 			break;
@@ -2436,6 +2447,12 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 		nopwrite = (!dedup && (zio_checksum_table[checksum].ci_flags &
 		    ZCHECKSUM_FLAG_NOPWRITE) &&
 		    compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled);
+
+		if (os->os_redundant_metadata == ZFS_REDUNDANT_METADATA_ALL ||
+		    (os->os_redundant_metadata ==
+		    ZFS_REDUNDANT_METADATA_MOST &&
+		    zfs_redundant_metadata_most_ditto_level <= 1))
+			gang_copies++;
 	}
 
 	/*
@@ -2452,6 +2469,7 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 
 		if (DMU_OT_IS_ENCRYPTED(type)) {
 			copies = MIN(copies, SPA_DVAS_PER_BP - 1);
+			gang_copies = MIN(gang_copies, SPA_DVAS_PER_BP - 1);
 			nopwrite = B_FALSE;
 		} else {
 			dedup = B_FALSE;
@@ -2469,6 +2487,7 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 	zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
 	zp->zp_level = level;
 	zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa));
+	zp->zp_gang_copies = MIN(gang_copies, spa_max_replication(os->os_spa));
 	zp->zp_dedup = dedup;
 	zp->zp_dedup_verify = dedup && dedup_verify;
 	zp->zp_nopwrite = nopwrite;
diff --git a/module/zfs/dmu_recv.c b/module/zfs/dmu_recv.c
index 91e3ca1cf..a636ae73b 100644
--- a/module/zfs/dmu_recv.c
+++ b/module/zfs/dmu_recv.c
@@ -2300,6 +2300,9 @@ flush_write_batch_impl(struct receive_writer_arg *rwa)
 					zp.zp_nopwrite = B_FALSE;
 					zp.zp_copies = MIN(zp.zp_copies,
 					    SPA_DVAS_PER_BP - 1);
+					zp.zp_gang_copies =
+					    MIN(zp.zp_gang_copies,
+					    SPA_DVAS_PER_BP - 1);
 				}
 				zio_flags |= ZIO_FLAG_RAW;
 			} else if (DRR_WRITE_COMPRESSED(drrw)) {
diff --git a/module/zfs/zio.c b/module/zfs/zio.c
index 50dbafa09..63f57cf26 100644
--- a/module/zfs/zio.c
+++ b/module/zfs/zio.c
@@ -1415,8 +1415,8 @@ zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, abd_t *data,
 }
 
 void
-zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite,
-    boolean_t brtwrite)
+zio_write_override(zio_t *zio, blkptr_t *bp, int copies, int gang_copies,
+    boolean_t nopwrite, boolean_t brtwrite)
 {
 	ASSERT(zio->io_type == ZIO_TYPE_WRITE);
 	ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
@@ -1433,6 +1433,7 @@ zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite,
 	zio->io_prop.zp_nopwrite = nopwrite;
 	zio->io_prop.zp_brtwrite = brtwrite;
 	zio->io_prop.zp_copies = copies;
+	zio->io_prop.zp_gang_copies = gang_copies;
 	zio->io_bp_override = bp;
 }
 
@@ -3140,15 +3141,13 @@ zio_write_gang_block(zio_t *pio, metaslab_class_t *mc)
 	boolean_t has_data = !(pio->io_flags & ZIO_FLAG_NODATA);
 
 	/*
-	 * If one copy was requested, store 2 copies of the GBH, so that we
-	 * can still traverse all the data (e.g. to free or scrub) even if a
-	 * block is damaged.  Note that we can't store 3 copies of the GBH in
-	 * all cases, e.g. with encryption, which uses DVA[2] for the IV+salt.
+	 * Store multiple copies of the GBH, so that we can still traverse
+	 * all the data (e.g. to free or scrub) even if a block is damaged.
+	 * This value respects the redundant_metadata property.
 	 */
-	int gbh_copies = copies;
-	if (gbh_copies == 1) {
-		gbh_copies = MIN(2, spa_max_replication(spa));
-	}
+	int gbh_copies = gio->io_prop.zp_gang_copies;
+	ASSERT3S(gbh_copies, >, 0);
+	ASSERT3S(gbh_copies, <=, SPA_DVAS_PER_BP);
 
 	ASSERT(ZIO_HAS_ALLOCATOR(pio));
 	int flags = METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER;
@@ -3168,6 +3167,7 @@ zio_write_gang_block(zio_t *pio, metaslab_class_t *mc)
 		 * since metaslab_class_throttle_reserve() always allows
 		 * additional reservations for gang blocks.
 		 */
+		ASSERT3U(gbh_copies, >=, copies);
 		VERIFY(metaslab_class_throttle_reserve(mc, gbh_copies - copies,
 		    pio->io_allocator, pio, flags));
 	}
@@ -3230,6 +3230,7 @@ zio_write_gang_block(zio_t *pio, metaslab_class_t *mc)
 		zp.zp_type = zp.zp_storage_type = DMU_OT_NONE;
 		zp.zp_level = 0;
 		zp.zp_copies = gio->io_prop.zp_copies;
+		zp.zp_gang_copies = gio->io_prop.zp_gang_copies;
 		zp.zp_dedup = B_FALSE;
 		zp.zp_dedup_verify = B_FALSE;
 		zp.zp_nopwrite = B_FALSE;
@@ -3950,7 +3951,7 @@ zio_ddt_write(zio_t *zio)
 	 * grow the DDT entry by to satisfy the request.
 	 */
 	zio_prop_t czp = *zp;
-	czp.zp_copies = need_dvas;
+	czp.zp_copies = czp.zp_gang_copies = need_dvas;
 	zio_t *cio = zio_write(zio, spa, txg, bp, zio->io_orig_abd,
 	    zio->io_orig_size, zio->io_orig_size, &czp,
 	    zio_ddt_child_write_ready, NULL,
diff --git a/tests/runfiles/common.run b/tests/runfiles/common.run
index 70b35e30e..1f8aca0d9 100644
--- a/tests/runfiles/common.run
+++ b/tests/runfiles/common.run
@@ -724,6 +724,10 @@ tests = ['large_dnode_001_pos', 'large_dnode_003_pos', 'large_dnode_004_neg',
     'large_dnode_005_pos', 'large_dnode_007_neg', 'large_dnode_009_pos']
 tags = ['functional', 'features', 'large_dnode']
 
+[tests/functional/gang_blocks]
+tests = ['gang_blocks_redundant']
+tags = ['functional', 'gang_blocks']
+
 [tests/functional/grow]
 pre =
 post =
diff --git a/tests/zfs-tests/include/tunables.cfg b/tests/zfs-tests/include/tunables.cfg
index 0a546dd44..79dc64ad9 100644
--- a/tests/zfs-tests/include/tunables.cfg
+++ b/tests/zfs-tests/include/tunables.cfg
@@ -64,6 +64,7 @@ MAX_DATASET_NESTING		max_dataset_nesting		zfs_max_dataset_nesting
 MAX_MISSING_TVDS		max_missing_tvds		zfs_max_missing_tvds
 METASLAB_DEBUG_LOAD		metaslab.debug_load		metaslab_debug_load
 METASLAB_FORCE_GANGING		metaslab.force_ganging		metaslab_force_ganging
+METASLAB_FORCE_GANGING_PCT	metaslab.force_ganging_pct	metaslab_force_ganging_pct
 MULTIHOST_FAIL_INTERVALS	multihost.fail_intervals	zfs_multihost_fail_intervals
 MULTIHOST_HISTORY		multihost.history		zfs_multihost_history
 MULTIHOST_IMPORT_INTERVALS	multihost.import_intervals	zfs_multihost_import_intervals
diff --git a/tests/zfs-tests/tests/Makefile.am b/tests/zfs-tests/tests/Makefile.am
index 0942082cf..bce546d06 100644
--- a/tests/zfs-tests/tests/Makefile.am
+++ b/tests/zfs-tests/tests/Makefile.am
@@ -275,6 +275,7 @@ nobase_dist_datadir_zfs_tests_tests_DATA += \
 	functional/events/events.cfg \
 	functional/events/events_common.kshlib \
 	functional/fault/fault.cfg \
+	functional/gang_blocks/gang_blocks.kshlib \
 	functional/grow/grow.cfg \
 	functional/history/history.cfg \
 	functional/history/history_common.kshlib \
@@ -1558,6 +1559,9 @@ nobase_dist_datadir_zfs_tests_tests_SCRIPTS += \
 	functional/features/large_dnode/large_dnode_008_pos.ksh \
 	functional/features/large_dnode/large_dnode_009_pos.ksh \
 	functional/features/large_dnode/setup.ksh \
+	functional/gang_blocks/cleanup.ksh \
+	functional/gang_blocks/gang_blocks_redundant.ksh \
+	functional/gang_blocks/setup.ksh \
 	functional/grow/grow_pool_001_pos.ksh \
 	functional/grow/grow_replicas_001_pos.ksh \
 	functional/history/cleanup.ksh \
diff --git a/tests/zfs-tests/tests/functional/gang_blocks/cleanup.ksh b/tests/zfs-tests/tests/functional/gang_blocks/cleanup.ksh
new file mode 100755
index 000000000..4ae6ec16f
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/gang_blocks/cleanup.ksh
@@ -0,0 +1,31 @@
+#!/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 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 (c) 2025 by Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+
+restore_tunable METASLAB_FORCE_GANGING
+restore_tunable METASLAB_FORCE_GANGING_PCT
+default_cleanup
diff --git a/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks.kshlib b/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks.kshlib
new file mode 100644
index 000000000..8799a1436
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks.kshlib
@@ -0,0 +1,120 @@
+#
+# 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 (c) 2025 By Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+
+#
+# Get 0th DVA of first L0 block of file
+#
+# $1 filesystem
+# $2 object number
+#
+function get_object_info
+{
+	typeset fs=$1
+	typeset obj=$2
+
+	zdb -dddddd $fs $obj
+}
+
+#
+# $1 filesystem
+# $2 path to file
+# $3 block filter
+#
+function get_blocks_filter
+{
+	typeset fs=$1
+	typeset path=$2
+
+	typeset full_path="$(get_prop mountpoint $fs)/$path"
+	typeset obj="$(ls -i $full_path | awk '{print $1}')"
+
+	get_object_info $fs $obj | grep $3 | grep -v Dataset
+}
+
+function get_first_block
+{
+	get_blocks_filter $1 $2 L0 | head -n 1
+}
+
+function get_first_block_dva
+{
+	get_first_block $1 $2 | sed 's/.*L0 \([^ ]*\).*/\1/'
+}
+
+# Takes a zdb compressed blkptr line on stdin
+function get_num_dvas
+{
+	sed 's/.*L[0-9] \(.*\) [a-f0-9]*L.*/\1/' | awk '{print NF}'
+}
+
+function check_gang_dva
+{
+	typeset last_byte="$(echo -n $1 | tail -c 1)"
+	[[ "$last_byte" == "G" ]] || return 1
+	return 0
+}
+
+function check_is_gang_dva
+{
+	check_gang_dva $1 || log_fail "Not a gang DVA: \"$1\""
+}
+
+function check_not_gang_dva
+{
+	check_gang_dva $1 && log_fail "Gang DVA: \"$1\""
+}
+
+#
+# Get the gang header contents of the given dva in the given pool
+#
+# $1 pool
+# $2 dva
+# $3 size (in hexidecimal)
+#
+function read_gang_header
+{
+	typeset pool=$1
+	typeset dva=$2
+	typeset size=$3
+
+	check_is_gang_dva $dva
+
+	zdb -R $pool "${dva%:*}:$size:g" 2>&1 | grep -v "Found vdev:"
+}
+
+function preamble
+{
+	save_tunable METASLAB_FORCE_GANGING
+	save_tunable METASLAB_FORCE_GANGING_PCT
+}
+
+function cleanup
+{
+	destroy_pool $TESTPOOL
+	restore_tunable METASLAB_FORCE_GANGING
+	restore_tunable METASLAB_FORCE_GANGING_PCT
+}
diff --git a/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks_redundant.ksh b/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks_redundant.ksh
new file mode 100755
index 000000000..1c44a7c5e
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/gang_blocks/gang_blocks_redundant.ksh
@@ -0,0 +1,88 @@
+#!/bin/ksh
+#
+# 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.
+#
+
+#
+# Copyright (c) 2025 by Klara Inc.
+#
+
+#
+# Description:
+# Verify that the redundant_metadata setting is respected by gang headers
+#
+# Strategy:
+# 1. Create a filesystem with redundant_metadata={all,most,some,none}
+# 2. Verify that gang blocks at different levels have the right amount of redundancy
+#
+
+. $STF_SUITE/include/libtest.shlib
+. $STF_SUITE/tests/functional/gang_blocks/gang_blocks.kshlib
+
+log_assert "Verify that gang blocks at different levels have the right amount of redundancy."
+
+function cleanup2
+{
+	for red in all most some none; do zfs destroy $TESTPOOL/$TESTFS-$red; done
+	cleanup
+}
+
+preamble
+log_onexit cleanup2
+
+log_must zpool create -f -o ashift=9 $TESTPOOL $DISKS
+set_tunable64 METASLAB_FORCE_GANGING 1500
+set_tunable32 METASLAB_FORCE_GANGING_PCT 100
+for red in all most some none; do
+	log_must zfs create -o redundant_metadata=$red -o recordsize=512 \
+		 $TESTPOOL/$TESTFS-$red
+	if [[ "$red" == "all" ]]; then
+		log_must zfs set recordsize=8k $TESTPOOL/$TESTFS-$red
+	fi
+	mountpoint=$(get_prop mountpoint $TESTPOOL/$TESTFS-$red)
+
+	path="${mountpoint}/file"
+	log_must dd if=/dev/urandom of=$path bs=1M count=1
+	log_must zpool sync $TESTPOOL
+	num_l0_dvas=$(get_first_block $TESTPOOL/$TESTFS-$red file | get_num_dvas)
+	if [[ "$red" == "all" ]]; then
+		[[ "$num_l0_dvas" -eq 2 ]] || \
+			log_fail "wrong number of DVAs for L0 in $red: $num_l0_dvas"
+	else
+		[[ "$num_l0_dvas" -eq 1 ]] || \
+			log_fail "wrong number of DVAs for L0 in $red: $num_l0_dvas"
+	fi
+
+	num_l1_dvas=$(get_blocks_filter $TESTPOOL/$TESTFS-$red file L1 | head -n 1 | get_num_dvas)
+	if [[ "$red" == "all" || "$red" == "most" ]]; then
+		[[ "$num_l1_dvas" -eq 2 ]] || \
+			log_fail "wrong number of DVAs for L1 in $red: $num_l1_dvas"
+	else
+		[[ "$num_l1_dvas" -eq 1 ]] || \
+			log_fail "wrong number of DVAs for L1 in $red: $num_l1_dvas"
+	fi
+
+	for i in `seq 1 80`; do
+		dd if=/dev/urandom of=/$mountpoint/f$i bs=512 count=1 2>/dev/null || log_fail "dd failed"
+	done
+	log_must zpool sync $TESTPOOL
+	obj_0_gangs=$(get_object_info $TESTPOOL/$TESTFS-$red 0 L0 | grep G)
+	num_obj_0_dvas=$(echo "$obj_0_gangs" | head -n 1 | get_num_dvas)
+	if [[ "$red" != "none" ]]; then
+		[[ "$num_obj_0_dvas" -eq 2 ]] || \
+			log_fail "wrong number of DVAs for obj 0 in $red: $num_obj_0_dvas"
+	else
+		[[ "$num_obj_0_dvas" -eq 1 ]] || \
+			log_fail "wrong number of DVAs for obj 0 in $red: $num_obj_0_dvas"
+	fi
+	log_note "Level $red passed"
+done
+
+log_pass "Gang blocks at different levels have the right amount of redundancy."
diff --git a/tests/zfs-tests/tests/functional/gang_blocks/setup.ksh b/tests/zfs-tests/tests/functional/gang_blocks/setup.ksh
new file mode 100755
index 000000000..0d2b239a0
--- /dev/null
+++ b/tests/zfs-tests/tests/functional/gang_blocks/setup.ksh
@@ -0,0 +1,30 @@
+#!/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 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 (c) 2025 by Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+
+set_tunable64 METASLAB_FORCE_GANGING 16777217
+set_tunable32 METASLAB_FORCE_GANGING_PCT 0