Intermediate changes

14 files changed, 167 insertions, 74 deletions

diff --git a/contrib/python/psutil/py2/ya.make b/contrib/python/psutil/py2/ya.make
index 0e3d24c4d0..6c4bb9e324 100644
--- a/contrib/python/psutil/py2/ya.make
+++ b/contrib/python/psutil/py2/ya.make
@@ -11,6 +11,7 @@ NO_LINT()
 NO_CHECK_IMPORTS(
     psutil._psaix
     psutil._psbsd
+    psutil._pslinux
     psutil._psosx
     psutil._pssunos
     psutil._psutil_bsd
diff --git a/contrib/python/psutil/py3/ya.make b/contrib/python/psutil/py3/ya.make
index 5ae4714a6a..3c2c3464ab 100644
--- a/contrib/python/psutil/py3/ya.make
+++ b/contrib/python/psutil/py3/ya.make
@@ -11,6 +11,7 @@ NO_LINT()
 NO_CHECK_IMPORTS(
     psutil._psaix
     psutil._psbsd
+    psutil._pslinux
     psutil._psosx
     psutil._pssunos
     psutil._psutil_bsd
diff --git a/yt/yt/client/api/admin_client.h b/yt/yt/client/api/admin_client.h
index f2bc941ca0..cf8d789c57 100644
--- a/yt/yt/client/api/admin_client.h
+++ b/yt/yt/client/api/admin_client.h
@@ -271,14 +271,14 @@ struct IAdminClient
         const std::vector<NObjectClient::TCellId>& cellIds,
         const TResumeTabletCellsOptions& options = {}) = 0;
 
-    virtual TFuture<TMaintenanceId> AddMaintenance(
+    virtual TFuture<TMaintenanceIdPerTarget> AddMaintenance(
         EMaintenanceComponent component,
         const TString& address,
         EMaintenanceType type,
         const TString& comment,
         const TAddMaintenanceOptions& options = {}) = 0;
 
-    virtual TFuture<TMaintenanceCounts> RemoveMaintenance(
+    virtual TFuture<TMaintenanceCountsPerTarget> RemoveMaintenance(
         EMaintenanceComponent component,
         const TString& address,
         const TMaintenanceFilter& filter,
diff --git a/yt/yt/client/api/delegating_client.h b/yt/yt/client/api/delegating_client.h
index bd7d8029fc..97d46ce93a 100644
--- a/yt/yt/client/api/delegating_client.h
+++ b/yt/yt/client/api/delegating_client.h
@@ -647,7 +647,7 @@ public:
         const TResumeTabletCellsOptions& options),
         (cellIds, options))
 
-    DELEGATE_METHOD(TFuture<TMaintenanceId>, AddMaintenance, (
+    DELEGATE_METHOD(TFuture<TMaintenanceIdPerTarget>, AddMaintenance, (
         EMaintenanceComponent component,
         const TString& address,
         EMaintenanceType type,
@@ -655,7 +655,7 @@ public:
         const TAddMaintenanceOptions& options),
         (component, address, type, comment, options))
 
-    DELEGATE_METHOD(TFuture<TMaintenanceCounts>, RemoveMaintenance, (
+    DELEGATE_METHOD(TFuture<TMaintenanceCountsPerTarget>, RemoveMaintenance, (
         EMaintenanceComponent component,
         const TString& address,
         const TMaintenanceFilter& filter,
diff --git a/yt/yt/client/api/public.h b/yt/yt/client/api/public.h
index 5f3db2e19a..d715976292 100644
--- a/yt/yt/client/api/public.h
+++ b/yt/yt/client/api/public.h
@@ -15,6 +15,7 @@
 #include <yt/yt/core/rpc/public.h>
 
 #include <library/cpp/yt/containers/enum_indexed_array.h>
+#include <library/cpp/yt/small_containers/compact_flat_map.h>
 
 namespace NYT::NApi {
 
@@ -221,6 +222,13 @@ DEFINE_ENUM(EMaintenanceComponent,
 using TMaintenanceId = TGuid;
 using TMaintenanceCounts = TEnumIndexedArray<EMaintenanceType, int>;
 
+// Almost always there is single maintenance target. The exception is virtual
+// "host" target which represents all nodes on a given host.
+constexpr int TypicalMaintenanceTargetCount = 1;
+
+using TMaintenanceIdPerTarget = TCompactFlatMap<TString, TMaintenanceId, TypicalMaintenanceTargetCount>;
+using TMaintenanceCountsPerTarget = TCompactFlatMap<TString, TMaintenanceCounts, TypicalMaintenanceTargetCount>;
+
 ////////////////////////////////////////////////////////////////////////////////
 
 } // namespace NYT::NApi
diff --git a/yt/yt/client/api/rpc_proxy/client_impl.cpp b/yt/yt/client/api/rpc_proxy/client_impl.cpp
index 6daa563030..99706535aa 100644
--- a/yt/yt/client/api/rpc_proxy/client_impl.cpp
+++ b/yt/yt/client/api/rpc_proxy/client_impl.cpp
@@ -1830,7 +1830,7 @@ NProto::EMaintenanceType ConvertMaintenanceTypeToProto(EMaintenanceType type)
 
 } // namespace
 
-TFuture<TMaintenanceId> TClient::AddMaintenance(
+TFuture<TMaintenanceIdPerTarget> TClient::AddMaintenance(
     EMaintenanceComponent component,
     const TString& address,
     EMaintenanceType type,
@@ -1848,13 +1848,28 @@ TFuture<TMaintenanceId> TClient::AddMaintenance(
     req->set_address(address);
     req->set_type(ConvertMaintenanceTypeToProto(type));
     req->set_comment(comment);
-
-    return req->Invoke().Apply(BIND([] (const TErrorOr<TApiServiceProxy::TRspAddMaintenancePtr>& rsp) {
-        return FromProto<TMaintenanceId>(rsp.ValueOrThrow()->id());
-    }));
+    req->set_supports_per_target_response(true);
+
+    return req->Invoke().Apply(BIND(
+        [address] (const TErrorOr<TApiServiceProxy::TRspAddMaintenancePtr>& rsp) {
+            const auto& value = rsp.ValueOrThrow();
+
+            TMaintenanceIdPerTarget result;
+
+            // COMPAT(kvk1920): Compatibility with pre-24.2 RPC proxies.
+            if (value->has_id()) {
+                result[address] = FromProto<TMaintenanceId>(value->id());
+            } else {
+                result.reserve(value->id_per_target_size());
+                for (const auto& [target, id] : value->id_per_target()) {
+                    result.insert({target, FromProto<TMaintenanceId>(id)});
+                }
+            }
+            return result;
+        }));
 }
 
-TFuture<TMaintenanceCounts> TClient::RemoveMaintenance(
+TFuture<TMaintenanceCountsPerTarget> TClient::RemoveMaintenance(
     EMaintenanceComponent component,
     const TString& address,
     const TMaintenanceFilter& filter,
@@ -1884,26 +1899,39 @@ TFuture<TMaintenanceCounts> TClient::RemoveMaintenance(
             req->set_user(user);
         });
 
-    return req->Invoke().Apply(BIND([] (const TErrorOr<TApiServiceProxy::TRspRemoveMaintenancePtr>& rsp) {
-        auto rspValue = rsp.ValueOrThrow();
-
-        const auto& protoCounts = rspValue->removed_maintenance_counts();
-        TMaintenanceCounts counts;
+    req->set_supports_per_target_response(true);
 
-        if (!rspValue->use_map_instead_of_fields()) {
-            counts[EMaintenanceType::Ban] = rspValue->ban();
-            counts[EMaintenanceType::Decommission] = rspValue->decommission();
-            counts[EMaintenanceType::DisableSchedulerJobs] = rspValue->disable_scheduler_jobs();
-            counts[EMaintenanceType::DisableWriteSessions] = rspValue->disable_write_sessions();
-            counts[EMaintenanceType::DisableTabletCells] = rspValue->disable_tablet_cells();
-            counts[EMaintenanceType::PendingRestart] = rspValue->pending_restart();
+    return req->Invoke().Apply(BIND([address] (const TErrorOr<TApiServiceProxy::TRspRemoveMaintenancePtr>& rsp) {
+        auto rspValue = rsp.ValueOrThrow();
+        TMaintenanceCountsPerTarget result;
+
+        // COMPAT(kvk1920): Compatibility with pre-24.2 RPC proxies.
+        if (!rspValue->supports_per_target_response()) {
+            auto& counts = result[address];
+            // COMPAT(kvk1920): Compatibility with pre-23.2 RPC proxies.
+            if (!rspValue->use_map_instead_of_fields()) {
+                counts[EMaintenanceType::Ban] = rspValue->ban();
+                counts[EMaintenanceType::Decommission] = rspValue->decommission();
+                counts[EMaintenanceType::DisableSchedulerJobs] = rspValue->disable_scheduler_jobs();
+                counts[EMaintenanceType::DisableWriteSessions] = rspValue->disable_write_sessions();
+                counts[EMaintenanceType::DisableTabletCells] = rspValue->disable_tablet_cells();
+                counts[EMaintenanceType::PendingRestart] = rspValue->pending_restart();
+            } else {
+                for (const auto& [type, count] : rspValue->removed_maintenance_counts()) {
+                    counts[CheckedEnumCast<EMaintenanceType>(type)] = count;
+                }
+            }
         } else {
-            for (auto [type, count] : protoCounts) {
-                counts[CheckedEnumCast<EMaintenanceType>(type)] = count;
+            result.reserve(rspValue->removed_maintenance_counts_per_target_size());
+            for (const auto& [target, protoCounts] : rspValue->removed_maintenance_counts_per_target()) {
+                auto& counts = result[target];
+                for (const auto& [type, count] : protoCounts.counts()) {
+                    counts[CheckedEnumCast<EMaintenanceType>(type)] = count;
+                }
             }
         }
 
-        return counts;
+        return result;
     }));
 }
 
diff --git a/yt/yt/client/api/rpc_proxy/client_impl.h b/yt/yt/client/api/rpc_proxy/client_impl.h
index addd0e5072..8dc59e06a0 100644
--- a/yt/yt/client/api/rpc_proxy/client_impl.h
+++ b/yt/yt/client/api/rpc_proxy/client_impl.h
@@ -394,14 +394,14 @@ public:
         const std::vector<NObjectClient::TCellId>& cellIds,
         const TResumeTabletCellsOptions& options) override;
 
-    TFuture<TMaintenanceId> AddMaintenance(
+    TFuture<TMaintenanceIdPerTarget> AddMaintenance(
         EMaintenanceComponent component,
         const TString& address,
         EMaintenanceType type,
         const TString& comment,
         const TAddMaintenanceOptions& options) override;
 
-    TFuture<TMaintenanceCounts> RemoveMaintenance(
+    TFuture<TMaintenanceCountsPerTarget> RemoveMaintenance(
         EMaintenanceComponent component,
         const TString& address,
         const TMaintenanceFilter& filter,
diff --git a/yt/yt/client/driver/admin_commands.cpp b/yt/yt/client/driver/admin_commands.cpp
index 7518352825..c1af19fc13 100644
--- a/yt/yt/client/driver/admin_commands.cpp
+++ b/yt/yt/client/driver/admin_commands.cpp
@@ -17,6 +17,10 @@ using namespace NObjectClient;
 
 using NApi::TMaintenanceId;
 using NApi::TMaintenanceFilter;
+using NApi::EMaintenanceType;
+using NApi::TMaintenanceCounts;
+using NApi::TMaintenanceCountsPerTarget;
+using NApi::TMaintenanceIdPerTarget;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -345,11 +349,15 @@ void TAddMaintenanceCommand::Register(TRegistrar registrar)
     registrar.Parameter("address", &TThis::Address_);
     registrar.Parameter("type", &TThis::Type_);
     registrar.Parameter("comment", &TThis::Comment_);
+
+    // COMPAT(kvk1920): For compatibility with pre-24.2 HTTP clients.
+    registrar.Parameter("supports_per_target_response", &TThis::SupportsPerTargetResponse_)
+        .Default(false);
 }
 
 void TAddMaintenanceCommand::DoExecute(ICommandContextPtr context)
 {
-    auto id = WaitFor(context->GetClient()->AddMaintenance(
+    auto response = WaitFor(context->GetClient()->AddMaintenance(
         Component_,
         Address_,
         Type_,
@@ -357,7 +365,23 @@ void TAddMaintenanceCommand::DoExecute(ICommandContextPtr context)
         Options))
         .ValueOrThrow();
 
-    ProduceSingleOutputValue(context, "id", id);
+    // COMPAT(kvk1920): Compatibility with pre-24.2 HTTP clients.
+    if (!SupportsPerTargetResponse_) {
+        ProduceSingleOutputValue(
+            context,
+            "id",
+            response.size() == 1 ? response.begin()->second : TMaintenanceId{});
+        return;
+    }
+
+    ProduceOutput(context, [&] (NYson::IYsonConsumer* consumer) {
+        BuildYsonFluently(consumer)
+            .BeginMap()
+                .DoFor(response, [] (auto fluent, const std::pair<TString, TMaintenanceId>& targetAndId) {
+                    fluent.Item(targetAndId.first).Value(targetAndId.second);
+                })
+            .EndMap();
+    });
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -384,6 +408,9 @@ void TRemoveMaintenanceCommand::Register(TRegistrar registrar)
     registrar.Parameter("all", &TThis::All_)
         .Optional();
 
+    registrar.Parameter("supports_per_target_response", &TThis::SupportsPerTargetResponse_)
+        .Default(false);
+
     registrar.Postprocessor([&] (TThis* config) {
         THROW_ERROR_EXCEPTION_IF(config->Id_ && config->Ids_,
             "At most one of {\"id\", \"ids\"} can be specified at the same time");
@@ -402,30 +429,6 @@ void TRemoveMaintenanceCommand::Register(TRegistrar registrar)
     });
 }
 
-namespace {
-
-TStringBuf MaintenanceTypeToString(NApi::EMaintenanceType type)
-{
-    switch (type) {
-        case NApi::EMaintenanceType::Ban:
-            return "ban";
-        case NApi::EMaintenanceType::Decommission:
-            return "decommission";
-        case NApi::EMaintenanceType::DisableSchedulerJobs:
-            return "disable_scheduler_jobs";
-        case NApi::EMaintenanceType::DisableWriteSessions:
-            return "disable_write_sessions";
-        case NApi::EMaintenanceType::DisableTabletCells:
-            return "disable_tablet_cells";
-        case NApi::EMaintenanceType::PendingRestart:
-            return "pending_restart";
-        default:
-            YT_ABORT();
-    }
-}
-
-} // namespace
-
 void TRemoveMaintenanceCommand::DoExecute(ICommandContextPtr context)
 {
     TMaintenanceFilter filter;
@@ -448,22 +451,49 @@ void TRemoveMaintenanceCommand::DoExecute(ICommandContextPtr context)
         filter.Type = *Type_;
     }
 
-    auto removedMaintenanceCounts = WaitFor(context->GetClient()->RemoveMaintenance(
+    auto response = WaitFor(context->GetClient()->RemoveMaintenance(
         Component_,
         Address_,
         filter,
         Options))
         .ValueOrThrow();
 
-    ProduceOutput(context, [&] (NYson::IYsonConsumer* consumer) {
-        auto fluent = BuildYsonFluently(consumer)
-            .BeginMap();
-        for (auto type : TEnumTraits<NApi::EMaintenanceType>::GetDomainValues()) {
-            if (removedMaintenanceCounts[type] > 0) {
-                fluent = fluent.Item(MaintenanceTypeToString(type)).Value(removedMaintenanceCounts[type]);
+    auto produceCounts = [] (auto fluent, const TMaintenanceCounts& counts) {
+        fluent
+            .BeginMap()
+                .DoFor(
+                    TEnumTraits<NApi::EMaintenanceType>::GetDomainValues(),
+                    [&] (auto fluent, EMaintenanceType type) {
+                        if (counts[type] > 0) {
+                            fluent.Item(Format("%lv", type)).Value(counts[type]);
+                        }
+                    })
+            .EndMap();
+    };
+
+    // COMPAT(kvk1920): Compatibility with pre-24.2 HTTP clients.
+    if (!SupportsPerTargetResponse_) {
+        TMaintenanceCounts totalCounts;
+        for (const auto& [target, counts] : response) {
+            for (auto type : TEnumTraits<EMaintenanceType>::GetDomainValues()) {
+                totalCounts[type] += counts[type];
             }
         }
-        fluent.EndMap();
+        ProduceOutput(context, [&] (NYson::IYsonConsumer* consumer) {
+            produceCounts(BuildYsonFluently(consumer), totalCounts);
+        });
+        return;
+    }
+
+    ProduceOutput(context, [&] (NYson::IYsonConsumer* consumer) {
+        BuildYsonFluently(consumer)
+            .BeginMap()
+                .DoFor(
+                    response,
+                    [&] (auto fluent, const std::pair<TString, TMaintenanceCounts>& targetWithCounts) {
+                        produceCounts(fluent.Item(targetWithCounts.first), targetWithCounts.second);
+                    })
+            .EndMap();
     });
 }
 
diff --git a/yt/yt/client/driver/admin_commands.h b/yt/yt/client/driver/admin_commands.h
index 4a52a34bbf..0665eb3494 100644
--- a/yt/yt/client/driver/admin_commands.h
+++ b/yt/yt/client/driver/admin_commands.h
@@ -254,6 +254,8 @@ private:
     TString Address_;
     NApi::EMaintenanceType Type_;
     TString Comment_;
+    // COMPAT(kvk1920): Compatibility with pre-24.2 HTTP clients.
+    bool SupportsPerTargetResponse_;
 
     void DoExecute(ICommandContextPtr context) override;
 };
@@ -277,6 +279,8 @@ private:
     std::optional<NApi::TMaintenanceId> Id_;
     std::optional<std::vector<NApi::TMaintenanceId>> Ids_;
     std::optional<NApi::EMaintenanceType> Type_;
+    // COMPAT(kvk1920): Compatibility with pre-24.2 HTTP clients.
+    bool SupportsPerTargetResponse_;
 
     void DoExecute(ICommandContextPtr context) override;
 };
diff --git a/yt/yt/client/driver/driver.cpp b/yt/yt/client/driver/driver.cpp
index dfc733e56c..94fd78bdf6 100644
--- a/yt/yt/client/driver/driver.cpp
+++ b/yt/yt/client/driver/driver.cpp
@@ -332,8 +332,8 @@ public:
         REGISTER_ALL(TSuspendTabletCellsCommand,           "suspend_tablet_cells",            Null,       Structured, false,  false);
         REGISTER_ALL(TResumeTabletCellsCommand,            "resume_tablet_cells",             Null,       Structured, false,  false);
 
-        REGISTER_ALL(TAddMaintenanceCommand,               "add_maintenance",                 Null,       Structured, true,   false);
-        REGISTER_ALL(TRemoveMaintenanceCommand,            "remove_maintenance",              Null,       Structured, true,   false);
+        REGISTER    (TAddMaintenanceCommand,               "add_maintenance",                 Null,       Structured, true,   false, ApiVersion4);
+        REGISTER    (TRemoveMaintenanceCommand,            "remove_maintenance",              Null,       Structured, true,   false, ApiVersion4);
         REGISTER_ALL(TDisableChunkLocationsCommand,        "disable_chunk_locations",         Null,       Structured, false,  false);
         REGISTER_ALL(TDestroyChunkLocationsCommand,        "destroy_chunk_locations",         Null,       Structured, false,  false);
         REGISTER_ALL(TResurrectChunkLocationsCommand,      "resurrect_chunk_locations",       Null,       Structured, false,  false);
diff --git a/yt/yt/client/federated/client.cpp b/yt/yt/client/federated/client.cpp
index f5ad0c462c..dad29ee6a5 100644
--- a/yt/yt/client/federated/client.cpp
+++ b/yt/yt/client/federated/client.cpp
@@ -405,8 +405,8 @@ public:
     UNIMPLEMENTED_METHOD(TFuture<void>, SuspendTabletCells, (const std::vector<NObjectClient::TCellId>&, const TSuspendTabletCellsOptions&));
     UNIMPLEMENTED_METHOD(TFuture<void>, ResumeTabletCells, (const std::vector<NObjectClient::TCellId>&, const TResumeTabletCellsOptions&));
     UNIMPLEMENTED_METHOD(TFuture<void>, UpdateChaosTableReplicaProgress, (NChaosClient::TReplicaId, const TUpdateChaosTableReplicaProgressOptions&));
-    UNIMPLEMENTED_METHOD(TFuture<TMaintenanceId>, AddMaintenance, (EMaintenanceComponent, const TString&, EMaintenanceType, const TString&, const TAddMaintenanceOptions&));
-    UNIMPLEMENTED_METHOD(TFuture<TMaintenanceCounts>, RemoveMaintenance, (EMaintenanceComponent, const TString&, const TMaintenanceFilter&, const TRemoveMaintenanceOptions&));
+    UNIMPLEMENTED_METHOD(TFuture<TMaintenanceIdPerTarget>, AddMaintenance, (EMaintenanceComponent, const TString&, EMaintenanceType, const TString&, const TAddMaintenanceOptions&));
+    UNIMPLEMENTED_METHOD(TFuture<TMaintenanceCountsPerTarget>, RemoveMaintenance, (EMaintenanceComponent, const TString&, const TMaintenanceFilter&, const TRemoveMaintenanceOptions&));
     UNIMPLEMENTED_METHOD(TFuture<TDisableChunkLocationsResult>, DisableChunkLocations, (const TString&, const std::vector<TGuid>&, const TDisableChunkLocationsOptions&));
     UNIMPLEMENTED_METHOD(TFuture<TDestroyChunkLocationsResult>, DestroyChunkLocations, (const TString&, bool, const std::vector<TGuid>&, const TDestroyChunkLocationsOptions&));
     UNIMPLEMENTED_METHOD(TFuture<TResurrectChunkLocationsResult>, ResurrectChunkLocations, (const TString&, const std::vector<TGuid>&, const TResurrectChunkLocationsOptions&));
diff --git a/yt/yt/client/hedging/hedging.cpp b/yt/yt/client/hedging/hedging.cpp
index 2baa914e95..0be20d47af 100644
--- a/yt/yt/client/hedging/hedging.cpp
+++ b/yt/yt/client/hedging/hedging.cpp
@@ -193,8 +193,8 @@ public:
     UNSUPPORTED_METHOD(TFuture<void>, ResumeTabletCells, (const std::vector<NObjectClient::TCellId>&, const TResumeTabletCellsOptions&));
     UNSUPPORTED_METHOD(TFuture<NChaosClient::TReplicationCardPtr>, GetReplicationCard, (NChaosClient::TReplicationCardId, const TGetReplicationCardOptions&));
     UNSUPPORTED_METHOD(TFuture<void>, UpdateChaosTableReplicaProgress, (NChaosClient::TReplicaId, const TUpdateChaosTableReplicaProgressOptions&));
-    UNSUPPORTED_METHOD(TFuture<TMaintenanceId>, AddMaintenance, (EMaintenanceComponent, const TString&, EMaintenanceType, const TString&, const TAddMaintenanceOptions&));
-    UNSUPPORTED_METHOD(TFuture<TMaintenanceCounts>, RemoveMaintenance, (EMaintenanceComponent, const TString&, const TMaintenanceFilter&, const TRemoveMaintenanceOptions&));
+    UNSUPPORTED_METHOD(TFuture<TMaintenanceIdPerTarget>, AddMaintenance, (EMaintenanceComponent, const TString&, EMaintenanceType, const TString&, const TAddMaintenanceOptions&));
+    UNSUPPORTED_METHOD(TFuture<TMaintenanceCountsPerTarget>, RemoveMaintenance, (EMaintenanceComponent, const TString&, const TMaintenanceFilter&, const TRemoveMaintenanceOptions&));
     UNSUPPORTED_METHOD(TFuture<TDisableChunkLocationsResult>, DisableChunkLocations, (const TString&, const std::vector<TGuid>&, const TDisableChunkLocationsOptions&));
     UNSUPPORTED_METHOD(TFuture<TDestroyChunkLocationsResult>, DestroyChunkLocations, (const TString&, bool, const std::vector<TGuid>&, const TDestroyChunkLocationsOptions&));
     UNSUPPORTED_METHOD(TFuture<TResurrectChunkLocationsResult>, ResurrectChunkLocations, (const TString&, const std::vector<TGuid>&, const TResurrectChunkLocationsOptions&));
diff --git a/yt/yt/client/unittests/mock/client.h b/yt/yt/client/unittests/mock/client.h
index c299bc01e9..4d081f3620 100644
--- a/yt/yt/client/unittests/mock/client.h
+++ b/yt/yt/client/unittests/mock/client.h
@@ -327,7 +327,7 @@ public:
         const TResumeTabletCellsOptions& options),
         (override));
 
-    MOCK_METHOD(TFuture<TMaintenanceId>, AddMaintenance, (
+    MOCK_METHOD(TFuture<TMaintenanceIdPerTarget>, AddMaintenance, (
         EMaintenanceComponent component,
         const TString& address,
         EMaintenanceType type,
@@ -335,7 +335,7 @@ public:
         const TAddMaintenanceOptions& options),
         (override));
 
-    MOCK_METHOD(TFuture<TMaintenanceCounts>, RemoveMaintenance, (
+    MOCK_METHOD(TFuture<TMaintenanceCountsPerTarget>, RemoveMaintenance, (
         EMaintenanceComponent component,
         const TString& address,
         const TMaintenanceFilter& filter,
diff --git a/yt/yt_proto/yt/client/api/rpc_proxy/proto/api_service.proto b/yt/yt_proto/yt/client/api/rpc_proxy/proto/api_service.proto
index f8977a71a4..860672c48f 100644
--- a/yt/yt_proto/yt/client/api/rpc_proxy/proto/api_service.proto
+++ b/yt/yt_proto/yt/client/api/rpc_proxy/proto/api_service.proto
@@ -1059,11 +1059,19 @@ message TReqAddMaintenance
     required string address = 2;
     required EMaintenanceType type = 3;
     required string comment = 4;
+
+    // COMPAT(kvk1920): For compatibility with pre-24.2 RPC clients.
+    optional bool supports_per_target_response = 5 [default = false];
 }
 
 message TRspAddMaintenance
 {
-    required NYT.NProto.TGuid id = 1; // TMaintenanceId
+    // COMPAT(kvk1920): For compatibility with pre-24.2 RPC clients.
+    optional NYT.NProto.TGuid id = 1; // TMaintenanceId
+
+    // Key: component address
+    // Value: TMaintenanceId
+    map<string, NYT.NProto.TGuid> id_per_target = 2;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -1076,22 +1084,35 @@ message TReqRemoveMaintenance
     optional EMaintenanceType type = 4;
     optional string user = 5;
     optional bool mine = 6 [default = false];
+
+    // COMPAT(kvk1920): Compatibility with pre-24.2 RPC clients.
+    optional bool supports_per_target_response = 7 [default = false];
 }
 
 message TRspRemoveMaintenance
 {
-    // COMPAT(kvk1920): Can be removed after all clients, proxies and masters will be updated.
+    // COMPAT(kvk1920): For compatibility with pre-23.2.
     optional int32 ban = 1;
     optional int32 decommission = 2;
     optional int32 disable_scheduler_jobs = 3;
     optional int32 disable_write_sessions = 4;
     optional int32 disable_tablet_cells = 5;
-
-    // COMPAT(kvk1920)
+    optional int32 pending_restart = 8;
     optional bool use_map_instead_of_fields = 6 [default = false];
+
+    // COMPAT(kvk1920): For compatibility with pre-24.2 RPC clients.
     map<int32, int32> removed_maintenance_counts = 7; // Key: EMaintenanceType
 
-    optional int32 pending_restart = 8;
+    // COMPAT(kvk1920): For compatibility with pre-24.2 RPC proxies.
+    optional bool supports_per_target_response = 9 [default = false];
+
+    message TMaintenanceCounts
+    {
+        map<int32, int32> counts = 1; // Key: EMaintenanceType
+    }
+
+    // Key: component address
+    map<string, TMaintenanceCounts> removed_maintenance_counts_per_target = 10;
 }
 
 ////////////////////////////////////////////////////////////////////////////////