diff --git a/ceph.spec.in b/ceph.spec.in
index 46d9aae02ae8..5e101ed119b6 100644
--- a/ceph.spec.in
+++ b/ceph.spec.in
@@ -2132,6 +2132,7 @@ fi
 %{_bindir}/rgw-gap-list-comparator
 %{_bindir}/rgw-orphan-list
 %{_bindir}/rgw-policy-check
+%{_bindir}/rgw-restore-bucket-index
 %{_mandir}/man8/radosgw.8*
 %{_mandir}/man8/rgw-policy-check.8*
 %dir %{_localstatedir}/lib/ceph/radosgw
diff --git a/debian/radosgw.install b/debian/radosgw.install
index 40940c0e1ac2..df522926619f 100644
--- a/debian/radosgw.install
+++ b/debian/radosgw.install
@@ -7,6 +7,7 @@ usr/bin/radosgw-token
 usr/bin/rgw-gap-list
 usr/bin/rgw-gap-list-comparator
 usr/bin/rgw-orphan-list
+usr/bin/rgw-restore-bucket-index
 usr/share/man/man8/ceph-diff-sorted.8
 usr/share/man/man8/radosgw.8
 usr/share/man/man8/rgw-orphan-list.8
diff --git a/src/rgw/CMakeLists.txt b/src/rgw/CMakeLists.txt
index 9d155a1728fc..34a346281850 100644
--- a/src/rgw/CMakeLists.txt
+++ b/src/rgw/CMakeLists.txt
@@ -578,4 +578,5 @@ install(PROGRAMS
   rgw-gap-list
   rgw-gap-list-comparator
   rgw-orphan-list
+  rgw-restore-bucket-index
   DESTINATION bin)
diff --git a/src/rgw/driver/rados/rgw_rados.cc b/src/rgw/driver/rados/rgw_rados.cc
index db546a3ca68f..e9e4f8dff5c5 100644
--- a/src/rgw/driver/rados/rgw_rados.cc
+++ b/src/rgw/driver/rados/rgw_rados.cc
@@ -3600,6 +3600,34 @@ int RGWRados::rewrite_obj(RGWBucketInfo& dest_bucket_info, const rgw_obj& obj, c
                        attrset, 0, real_time(), NULL, dpp, y);
 }
 
+int RGWRados::reindex_obj(const RGWBucketInfo& bucket_info,
+			  const rgw_obj& obj,
+			  const DoutPrefixProvider* dpp,
+			  optional_yield y)
+{
+  if (bucket_info.versioned()) {
+    ldpp_dout(dpp, 10) << "WARNING: " << __func__ <<
+      ": cannot process versioned bucket \"" <<
+      bucket_info.bucket.get_key() << "\"" <<
+      dendl;
+    return -ENOTSUP;
+  }
+
+  Bucket target(this, bucket_info);
+  RGWRados::Bucket::UpdateIndex update_idx(&target, obj);
+  const std::string* no_write_tag = nullptr;
+
+  int ret = update_idx.prepare(dpp, RGWModifyOp::CLS_RGW_OP_ADD, no_write_tag, y);
+  if (ret < 0) {
+    ldpp_dout(dpp, 0) << "ERROR: " << __func__ <<
+      ": update index prepare for \"" << obj << "\" returned: " <<
+      cpp_strerror(-ret) << dendl;
+    return ret;
+  }
+
+  return 0;
+}
+
 struct obj_time_weight {
   real_time mtime;
   uint32_t zone_short_id;
diff --git a/src/rgw/driver/rados/rgw_rados.h b/src/rgw/driver/rados/rgw_rados.h
index 043e9569e816..96244b15a4ab 100644
--- a/src/rgw/driver/rados/rgw_rados.h
+++ b/src/rgw/driver/rados/rgw_rados.h
@@ -1085,6 +1085,10 @@ class RGWRados
   D3nDataCache* d3n_data_cache{nullptr};
 
   int rewrite_obj(RGWBucketInfo& dest_bucket_info, const rgw_obj& obj, const DoutPrefixProvider *dpp, optional_yield y);
+  int reindex_obj(const RGWBucketInfo& dest_bucket_info,
+		  const rgw_obj& obj,
+		  const DoutPrefixProvider* dpp,
+		  optional_yield y);
 
   int stat_remote_obj(const DoutPrefixProvider *dpp,
                RGWObjectCtx& obj_ctx,
diff --git a/src/rgw/rgw-restore-bucket-index b/src/rgw/rgw-restore-bucket-index
new file mode 100755
index 000000000000..e8503ca47562
--- /dev/null
+++ b/src/rgw/rgw-restore-bucket-index
@@ -0,0 +1,193 @@
+#!/usr/bin/env bash
+
+# version 2023-03-07
+
+# rgw-restore-bucket-index is an EXPERIMENTAL tool to use in case
+# bucket index entries for objects in the bucket are somehow lost. It
+# is expected to be needed and used rarely. A bucket name is provided
+# and the data pool for that bucket is scanned for all head objects
+# matching the bucket's marker. The rgw object name is then extracted
+# from the rados object name, and `radosgw-admin bucket reindex ...`
+# is used to add the bucket index entry.
+#
+# Because this script must process json objects, the `jq` tool must be
+# installed on the system.
+#
+# Usage: $0 [--proceed] <bucket-name> [data-pool-name]
+#
+# This tool is designed to be interactive, allowing the user to
+# examine the list of objects to be reindexed before
+# proceeding. However, if the "--proceed" option is provided, the
+# script will not prompt the user and simply proceed.
+
+trap "clean ; exit 1" TERM
+export TOP_PID=$$
+
+# IMPORTANT: affects order produced by 'sort' and 'ceph-diff-sorted'
+# relies on this ordering
+export LC_ALL=C
+
+export bkt_entry=/tmp/rgwrbi-bkt-entry.$$
+export bkt_inst=/tmp/rgwrbi-bkt-inst.$$
+export bkt_inst_new=/tmp/rgwrbi-bkt-inst-new.$$
+export obj_list=/tmp/rgwrbi-object-list.$$
+export zone_info=/tmp/rgwrbi-zone-info.$$
+export clean_temps=1
+
+# make sure jq is available
+if which jq > /dev/null ;then
+  :
+else
+  echo 'Error: must have command `jq` installed and on $PATH for json parsing.'
+  exit 1
+fi
+
+clean() {
+  if [ -n "$clean_temps" ] ;then
+    rm -f $bkt_entry $bkt_inst $bkt_inst_new $obj_list $zone_info
+  fi
+}
+
+super_exit() {
+   kill -s TERM $TOP_PID
+}
+
+usage() {
+  >&2 cat << EOF
+
+Usage: $0 [--proceed] <bucket-name> [data-pool-name]
+  NOTE: This tool is currently considered EXPERIMENTAL.
+  NOTE: If a data-pool-name is not supplied then it will be inferred from bucket and zone information.
+  NOTE: If --proceed is provided then user will not be prompted to proceed. Use with caution.
+EOF
+  super_exit
+}
+
+# strips the starting and ending double quotes from a string, so:
+#   "dog"   -> dog
+#   "dog    -> "dog
+#   d"o"g   -> d"o"g
+#   "do"g"  -> do"g
+strip_quotes() {
+  echo "$1" | sed 's/^"\(.*\)"$/\1/'
+}
+
+# Determines the name of the data pool. Expects the optional
+# command-line argument to appear as $1 if there is one. The
+# command-line has the highest priority, then the "explicit_placement"
+# in the bucket instance data, and finally the "placement_rule" in the
+# bucket instance data.
+get_pool() {
+  # command-line
+  if [ -n "$1" ] ;then
+    echo "$1"
+    exit 0
+  fi
+
+  # explicit_placement
+  expl_pool=$(strip_quotes $(jq '.data.bucket_info.bucket.explicit_placement.data_pool' $bkt_inst))
+  if [ -n "$expl_pool" ] ;then
+    echo "$expl_pool"
+    exit 0
+  fi
+
+  # placement_rule
+  plmt_rule=$(strip_quotes $(jq '.data.bucket_info.placement_rule' $bkt_inst))
+  plmt_pool=$(echo "$plmt_rule" | awk -F / '{print $1}')
+  plmt_class=$(echo "$plmt_rule" | awk -F / '{print $2}')
+  if [ -z "$plmt_class" ] ;then
+    plmt_class=STANDARD
+  fi
+
+  radosgw-admin zone get >$zone_info 2>/dev/null
+  pool=$(strip_quotes $(jq ".placement_pools [] | select(.key | contains(\"${plmt_pool}\")) .val .storage_classes.${plmt_class}.data_pool" $zone_info))
+
+  if [ -z "$pool" ] ;then
+      echo ERROR: unable to determine pool.
+      super_exit
+  fi
+  echo "$pool"
+}
+
+if [ $1 == "--proceed" ] ;then
+    echo "NOTICE: This tool is currently considered EXPERIMENTAL."
+    proceed=1
+    shift
+fi
+
+# expect 1 or 2 arguments
+if [ $# -eq 0 -o $# -gt 2 ] ;then
+   usage
+fi
+
+bucket=$1
+
+# read bucket entry metadata
+radosgw-admin metadata get bucket:$bucket >$bkt_entry 2>/dev/null
+marker=$(strip_quotes $(jq ".data.bucket.marker" $bkt_entry))
+bucket_id=$(strip_quotes $(jq ".data.bucket.bucket_id" $bkt_entry))
+echo marker is $marker
+echo bucket_id is $bucket_id
+
+# read bucket instance metadata
+radosgw-admin metadata get bucket.instance:${bucket}:$bucket_id >$bkt_inst 2>/dev/null
+
+# handle versioned buckets
+bkt_flags=$(jq ".data.bucket_info.flags" $bkt_inst)
+is_versioned=$(( $bkt_flags & 2)) # mask bit indicating it's a versioned bucket
+if [ "$is_versioned" -ne 0 ] ;then
+   echo "Error: this bucket appears to be versioned, and this tool cannot work with versioned buckets."
+   clean
+   exit 1
+fi
+
+# examine number of bucket index shards
+num_shards=$(jq ".data.bucket_info.num_shards" $bkt_inst)
+echo number of bucket index shards is $num_shards
+
+# determine data pool
+pool=$(get_pool $2)
+echo data pool is $pool
+
+# search the data pool for all of the head objects that begin with the
+# marker that are not in namespaces (indicated by an extra underscore)
+# and then strip away all but the rgw object name
+( rados -p $pool ls | grep "^${marker}_[^_]" | sed "s/^${marker}_\(.*\)/\1/" >$obj_list ) 2>/dev/null
+
+# handle the case where the resulting object list file is empty
+if [ -s $obj_list ] ;then
+  :
+else
+  echo "NOTICE: No head objects for bucket \"$bucket\" were found in pool \"$pool\", so nothing was recovered."
+  clean
+  exit 0
+fi
+
+if [ -z "$proceed" ] ;then
+    # warn user and get permission to proceed
+    echo "NOTICE: This tool is currently considered EXPERIMENTAL."
+    echo "The list of objects that we will attempt to restore can be found in \"$obj_list\"."
+    echo "Please review the object names in that file (either below or in another window/terminal) before proceeding."
+    while true ; do
+	read -p "Type \"proceed!\" to proceed, \"view\" to view object list, or \"q\" to quit: " action
+	if [ "$action" == "q" ] ;then
+	    echo "Exiting..."
+	    clean
+	    exit 0
+	elif [ "$action" == "view" ] ;then
+	    echo "Viewing..."
+	    less $obj_list
+	elif [ "$action" == "proceed!" ] ;then
+	    echo "Proceeding..."
+	    break
+	else
+	    echo "Error: response \"$action\" is not understood."
+	fi
+    done
+fi
+
+# execute object rewrite on all of the head objects
+radosgw-admin object reindex --bucket=$bucket --objects-file=$obj_list 2>/dev/null
+
+clean
+echo Done
diff --git a/src/rgw/rgw_admin.cc b/src/rgw/rgw_admin.cc
index 32eb80b19d1b..1c0304d81411 100644
--- a/src/rgw/rgw_admin.cc
+++ b/src/rgw/rgw_admin.cc
@@ -72,6 +72,7 @@ extern "C" {
 #include "services/svc_zone.h"
 
 #include "driver/rados/rgw_bucket.h"
+#include "driver/rados/rgw_sal_rados.h"
 
 #define dout_context g_ceph_context
 
@@ -171,6 +172,7 @@ void usage()
   cout << "  object stat                stat an object for its metadata\n";
   cout << "  object unlink              unlink object from bucket index\n";
   cout << "  object rewrite             rewrite the specified object\n";
+  cout << "  object reindex             reindex the object(s) indicated by --bucket and either --object or --objects-file\n";
   cout << "  objects expire             run expired objects cleanup\n";
   cout << "  objects expire-stale list  list stale expired objects (caused by reshard)\n";
   cout << "  objects expire-stale rm    remove stale expired objects\n";
@@ -340,6 +342,7 @@ void usage()
   cout << "   --bucket=<bucket>         Specify the bucket name. Also used by the quota command.\n";
   cout << "   --pool=<pool>             Specify the pool name. Also used to scan for leaked rados objects.\n";
   cout << "   --object=<object>         object name\n";
+  cout << "   --objects-file=<file>     file containing a list of object names to process\n";
   cout << "   --object-version=<version>         object version\n";
   cout << "   --date=<date>             date in the format yyyy-mm-dd\n";
   cout << "   --start-date=<date>       start date in the format yyyy-mm-dd\n";
@@ -425,7 +428,7 @@ void usage()
   cout << "   --show-log-sum=<flag>     enable/disable dump of log summation on log show\n";
   cout << "   --skip-zero-entries       log show only dumps entries that don't have zero value\n";
   cout << "                             in one of the numeric field\n";
-  cout << "   --infile=<file>           specify a file to read in when setting data\n";
+  cout << "   --infile=<file>           file to read in when setting data\n";
   cout << "   --categories=<list>       comma separated list of categories, used in usage show\n";
   cout << "   --caps=<caps>             list of caps (e.g., \"usage=read, write; user=read\")\n";
   cout << "   --op-mask=<op-mask>       permission of user's operations (e.g., \"read, write, delete, *\")\n";
@@ -682,6 +685,7 @@ enum class OPT {
   OBJECT_UNLINK,
   OBJECT_STAT,
   OBJECT_REWRITE,
+  OBJECT_REINDEX,
   OBJECTS_EXPIRE,
   OBJECTS_EXPIRE_STALE_LIST,
   OBJECTS_EXPIRE_STALE_RM,
@@ -898,6 +902,7 @@ static SimpleCmd::Commands all_cmds = {
   { "object unlink", OPT::OBJECT_UNLINK },
   { "object stat", OPT::OBJECT_STAT },
   { "object rewrite", OPT::OBJECT_REWRITE },
+  { "object reindex", OPT::OBJECT_REINDEX },
   { "objects expire", OPT::OBJECTS_EXPIRE },
   { "objects expire-stale list", OPT::OBJECTS_EXPIRE_STALE_LIST },
   { "objects expire-stale rm", OPT::OBJECTS_EXPIRE_STALE_RM },
@@ -3402,6 +3407,7 @@ int main(int argc, const char **argv)
   string op_mask_str;
   string quota_scope;
   string ratelimit_scope;
+  std::string objects_file;
   string object_version;
   string placement_id;
   std::optional<string> opt_storage_class;
@@ -3579,6 +3585,8 @@ int main(int argc, const char **argv)
       pool = rgw_pool(pool_name);
     } else if (ceph_argparse_witharg(args, i, &val, "-o", "--object", (char*)NULL)) {
       object = val;
+    } else if (ceph_argparse_witharg(args, i, &val, "--objects-file", (char*)NULL)) {
+      objects_file = val;
     } else if (ceph_argparse_witharg(args, i, &val, "--object-version", (char*)NULL)) {
       object_version = val;
     } else if (ceph_argparse_witharg(args, i, &val, "--client-id", (char*)NULL)) {
@@ -7774,7 +7782,81 @@ int main(int argc, const char **argv)
     } else {
       ldpp_dout(dpp(), 20) << "skipped object" << dendl;
     }
-  }
+  } // OPT::OBJECT_REWRITE
+
+  if (opt_cmd == OPT::OBJECT_REINDEX) {
+    if (bucket_name.empty()) {
+      cerr << "ERROR: --bucket not specified." << std::endl;
+      return EINVAL;
+    }
+    if (object.empty() && objects_file.empty()) {
+      cerr << "ERROR: neither --object nor --objects-file specified." << std::endl;
+      return EINVAL;
+    } else if (!object.empty() && !objects_file.empty()) {
+      cerr << "ERROR: both --object and --objects-file specified and only one is allowed." << std::endl;
+      return EINVAL;
+    } else if (!objects_file.empty() && !object_version.empty()) {
+      cerr << "ERROR: cannot specify --object_version when --objects-file specified." << std::endl;
+      return EINVAL;
+    }
+
+    int ret = init_bucket(user.get(), tenant, bucket_name, bucket_id, &bucket);
+    if (ret < 0) {
+      cerr << "ERROR: could not init bucket: " << cpp_strerror(-ret) <<
+	"." << std::endl;
+      return -ret;
+    }
+
+    rgw::sal::RadosStore* rados_store = dynamic_cast<rgw::sal::RadosStore*>(driver);
+    if (!rados_store) {
+      cerr <<
+	"ERROR: this command can only work when the cluster has a RADOS backing store." <<
+	std::endl;
+      return EPERM;
+    }
+    RGWRados* store = rados_store->getRados();
+
+    auto process = [&](const std::string& p_object, const std::string& p_object_version) -> int {
+      std::unique_ptr<rgw::sal::Object> obj = bucket->get_object(p_object);
+      obj->set_instance(p_object_version);
+      ret = store->reindex_obj(bucket->get_info(), obj->get_obj(), dpp(), null_yield);
+      if (ret < 0) {
+	return ret;
+      }
+      return 0;
+    };
+
+    if (!object.empty()) {
+      ret = process(object, object_version);
+      if (ret < 0) {
+	return -ret;
+      }
+    } else {
+      std::ifstream file;
+      file.open(objects_file);
+      if (!file.is_open()) {
+	std::cerr << "ERROR: unable to open objects-file \"" <<
+	  objects_file << "\"." << std::endl;
+	return ENOENT;
+      }
+
+      std::string obj_name;
+      const std::string empty_version;
+      while (std::getline(file, obj_name)) {
+	ret = process(obj_name, empty_version);
+	if (ret < 0) {
+	  std::cerr << "ERROR: while processing \"" << obj_name <<
+	    "\", received " << cpp_strerror(-ret) << "." << std::endl;
+	  if (!yes_i_really_mean_it) {
+	    std::cerr <<
+	      "NOTE: with *caution* you can use --yes-i-really-mean-it to push through errors and continue processing." <<
+	      std::endl;
+	    return -ret;
+	  }
+	}
+      } // while
+    }
+  } // OPT::OBJECT_REINDEX
 
   if (opt_cmd == OPT::OBJECTS_EXPIRE) {
     if (!static_cast<rgw::sal::RadosStore*>(driver)->getRados()->process_expire_objects(dpp())) {
diff --git a/src/test/cli/radosgw-admin/help.t b/src/test/cli/radosgw-admin/help.t
index 6c987c413ecb..72b14c09c835 100644
--- a/src/test/cli/radosgw-admin/help.t
+++ b/src/test/cli/radosgw-admin/help.t
@@ -42,6 +42,7 @@
     object stat                stat an object for its metadata
     object unlink              unlink object from bucket index
     object rewrite             rewrite the specified object
+    object reindex             reindex the object(s) indicated by --bucket and either --object or --objects-file
     objects expire             run expired objects cleanup
     objects expire-stale list  list stale expired objects (caused by reshard)
     objects expire-stale rm    remove stale expired objects
@@ -211,6 +212,7 @@
      --bucket=<bucket>         Specify the bucket name. Also used by the quota command.
      --pool=<pool>             Specify the pool name. Also used to scan for leaked rados objects.
      --object=<object>         object name
+     --objects-file=<file>     file containing a list of object names to process
      --object-version=<version>         object version
      --date=<date>             date in the format yyyy-mm-dd
      --start-date=<date>       start date in the format yyyy-mm-dd
@@ -296,7 +298,7 @@
      --show-log-sum=<flag>     enable/disable dump of log summation on log show
      --skip-zero-entries       log show only dumps entries that don't have zero value
                                in one of the numeric field
-     --infile=<file>           specify a file to read in when setting data
+     --infile=<file>           file to read in when setting data
      --categories=<list>       comma separated list of categories, used in usage show
      --caps=<caps>             list of caps (e.g., "usage=read, write; user=read")
      --op-mask=<op-mask>       permission of user's operations (e.g., "read, write, delete, *")