do not VERIFY on NODATA while discovering blobs at followers KIKIMR-12560

REVIEW: 2578469

REVIEW: 2584092
x-ydb-stable-ref: a5a4bf50de4a36bc455a545a57f286e348724eb7

15 files changed, 67 insertions, 47 deletions

diff --git a/ydb/core/base/blobstorage.h b/ydb/core/base/blobstorage.h
index d7cd026c81..f58906acee 100644
--- a/ydb/core/base/blobstorage.h
+++ b/ydb/core/base/blobstorage.h
@@ -1565,15 +1565,18 @@ struct TEvBlobStorage {
         const bool ReadBody;
         const bool DiscoverBlockedGeneration;
         const ui32 ForceBlockedGeneration;
+        const bool FromLeader;
         ui32 RestartCounter = 0;
 
-        TEvDiscover(ui64 tabletId, ui32 minGeneration, bool readBody, bool discoverBlockedGeneration, TInstant deadline, ui32 forceBlockedGeneration)
+        TEvDiscover(ui64 tabletId, ui32 minGeneration, bool readBody, bool discoverBlockedGeneration,
+                TInstant deadline, ui32 forceBlockedGeneration, bool fromLeader)
             : TabletId(tabletId)
             , MinGeneration(minGeneration)
             , Deadline(deadline)
             , ReadBody(readBody)
             , DiscoverBlockedGeneration(discoverBlockedGeneration)
             , ForceBlockedGeneration(forceBlockedGeneration)
+            , FromLeader(fromLeader)
         {}
 
         TString Print(bool isFull) const {
@@ -1583,6 +1586,8 @@ struct TEvBlobStorage {
             str << " MinGeneration# " << MinGeneration;
             str << " ReadBody# " << (ReadBody ? "true" : "false");
             str << " DiscoverBlockedGeneration# " << (DiscoverBlockedGeneration ? "true" : "false");
+            str << " ForceBlockedGeneration# " << ForceBlockedGeneration;
+            str << " FromLeader# " << (FromLeader ? "true" : "false");
             str << " Deadline# " << Deadline.MilliSeconds();
             str << "}";
             return str.Str();
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
index 2605a19a2e..1f810a385d 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
@@ -292,6 +292,7 @@ class TBlobStorageGroupDiscoverRequest : public TBlobStorageGroupRequestActor<TB
     ui64 TotalRecieved = 0;
 
     const ui32 ForceBlockedGeneration;
+    const bool FromLeader;
 
     template<typename TPtr>
     void SendResult(TPtr& result) {
@@ -802,18 +803,22 @@ class TBlobStorageGroupDiscoverRequest : public TBlobStorageGroupRequestActor<TB
                         << " GetBlockErrors# " << GetBlockErrors
                         << " VGetBlockedGen# " << VGetBlockedGen
                         << " Get.BlockedGeneration# " << msg->BlockedGeneration
+                        << " FromLeader# " << (FromLeader ? "true" : "false")
                         << " response status# NODATA, Reply with ERROR! "
                         << " looks like we have !!! LOST THE BLOB !!! id# " << response.Id.ToString();
 
                     R_LOG_ALERT_S("BSD18", str.Str());
-                    Sleep(TDuration::Seconds(1));
-                    str << " logacc# ";
-                    LogCtx.LogAcc.Output(str);
-                    str << " verboseNoData# ";
-                    str << msg->DebugInfo;
 
-                    Y_VERIFY(false, "%s", str.Str().data());
-                    // TODO: Remove the lines above
+                    if (FromLeader) {
+                        Sleep(TDuration::Seconds(1));
+
+                        str << " logacc# ";
+                        LogCtx.LogAcc.Output(str);
+                        str << " verboseNoData# ";
+                        str << msg->DebugInfo;
+
+                        Y_VERIFY(false, "%s", str.Str().data());
+                    }
 
                     IsGetDataDone = true;
                     if (IsGetBlockDone) {
@@ -868,7 +873,7 @@ class TBlobStorageGroupDiscoverRequest : public TBlobStorageGroupRequestActor<TB
     std::unique_ptr<IEventBase> RestartQuery(ui32 counter) {
         ++*Mon->NodeMon->RestartDiscover;
         auto ev = std::make_unique<TEvBlobStorage::TEvDiscover>(TabletId, MinGeneration, ReadBody, DiscoverBlockedGeneration,
-            Deadline, ForceBlockedGeneration);
+            Deadline, ForceBlockedGeneration, FromLeader);
         ev->RestartCounter = counter;
         return ev;
     }
@@ -902,6 +907,7 @@ public:
         , GroupResponseTracker(Info)
         , IsGetBlockDone(!DiscoverBlockedGeneration)
         , ForceBlockedGeneration(ev->ForceBlockedGeneration)
+        , FromLeader(ev->FromLeader)
     {}
 
     void Bootstrap() {
@@ -912,6 +918,7 @@ public:
             << " MinGeneration# " << MinGeneration
             << " ReadBody# " << (ReadBody ? "true" : "false")
             << " Deadline# " << Deadline
+            << " FromLeader# " << (FromLeader ? "true" : "false")
             << " RestartCounter# " << RestartCounter);
 
         const ui32 groupId = Info->GroupID;
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
index a4e48dba76..7c10b1e25a 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
@@ -427,6 +427,7 @@ class TBlobStorageGroupMirror3dcDiscoverRequest : public TBlobStorageGroupReques
     const bool ReadBody;
     const bool DiscoverBlockedGeneration;
     const ui32 ForceBlockedGeneration;
+    const bool FromLeader;
 
     std::unique_ptr<TDiscoverWorker> Worker;
     TVector<std::unique_ptr<TEvBlobStorage::TEvVGet>> Msgs;
@@ -469,13 +470,14 @@ public:
         , ReadBody(ev->ReadBody)
         , DiscoverBlockedGeneration(ev->DiscoverBlockedGeneration)
         , ForceBlockedGeneration(ev->ForceBlockedGeneration)
+        , FromLeader(ev->FromLeader)
         , GetBlockTracker(Info.Get())
     {}
 
     std::unique_ptr<IEventBase> RestartQuery(ui32 counter) {
         ++*Mon->NodeMon->RestartDiscover;
         auto ev = std::make_unique<TEvBlobStorage::TEvDiscover>(TabletId, MinGeneration, ReadBody, DiscoverBlockedGeneration,
-            Deadline, ForceBlockedGeneration);
+            Deadline, ForceBlockedGeneration, FromLeader);
         ev->RestartCounter = counter;
         return ev;
     }
@@ -490,6 +492,7 @@ public:
             << " ReadBody# " << (ReadBody ? "true" : "false")
             << " DiscoverBlockedGeneration# " << (DiscoverBlockedGeneration ? "true" : "false")
             << " ForceBlockedGeneration# " << ForceBlockedGeneration
+            << " FromLeader# " << (FromLeader ? "true" : "false")
             << " RestartCounter# " << RestartCounter);
 
         Worker = std::make_unique<TDiscoverWorker>(Info, TabletId, MinGeneration, ForceBlockedGeneration);
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
index 9e3393070a..22412d0081 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
@@ -18,6 +18,7 @@ class TBlobStorageGroupMirror3of4DiscoverRequest
     const bool ReadBody;
     const bool DiscoverBlockedGeneration;
     const ui32 ForceBlockedGeneration;
+    const bool FromLeader;
 
 public:
     static const auto& ActiveCounter(const TIntrusivePtr<TBlobStorageGroupProxyMon>& mon) {
@@ -43,6 +44,7 @@ public:
         , ReadBody(ev->ReadBody)
         , DiscoverBlockedGeneration(ev->DiscoverBlockedGeneration)
         , ForceBlockedGeneration(ev->ForceBlockedGeneration)
+        , FromLeader(ev->FromLeader)
     {
         for (size_t i = 0; i < DiskState.size(); ++i) {
             TDiskState& disk = DiskState[i];
@@ -54,7 +56,7 @@ public:
     std::unique_ptr<IEventBase> RestartQuery(ui32 counter) {
         ++*Mon->NodeMon->RestartDiscover;
         auto ev = std::make_unique<TEvBlobStorage::TEvDiscover>(TabletId, MinGeneration, ReadBody,
-            DiscoverBlockedGeneration, Deadline, ForceBlockedGeneration);
+            DiscoverBlockedGeneration, Deadline, ForceBlockedGeneration, FromLeader);
         ev->RestartCounter = counter;
         return ev;
     }
@@ -67,6 +69,7 @@ public:
             << " ReadBody# " << (ReadBody ? "true" : "false")
             << " DiscoverBlockedGeneration# " << (DiscoverBlockedGeneration ? "true" : "false")
             << " ForceBlockedGeneration# " << ForceBlockedGeneration
+            << " FromLeader# " << (FromLeader ? "true" : "false")
             << " RestartCounter# " << RestartCounter);
 
         Become(&TThis::StateFunc);
diff --git a/ydb/core/blobstorage/dsproxy/ut/dsproxy_fault_tolerance_ut_discover.h b/ydb/core/blobstorage/dsproxy/ut/dsproxy_fault_tolerance_ut_discover.h
index 2e8df42324..7d93d73c65 100644
--- a/ydb/core/blobstorage/dsproxy/ut/dsproxy_fault_tolerance_ut_discover.h
+++ b/ydb/core/blobstorage/dsproxy/ut/dsproxy_fault_tolerance_ut_discover.h
@@ -69,7 +69,7 @@ public:
 
             SetFailedDisks(failedDisks);
             SendToBSProxy(GetActorContext(), Info->GroupID, new TEvBlobStorage::TEvDiscover(tabletId, 0, false, false,
-                TInstant::Max(), 0));
+                TInstant::Max(), 0, true));
             auto resp = WaitForSpecificEvent<TEvBlobStorage::TEvDiscoverResult>();
 
             const NKikimrProto::EReplyStatus status = resp->Get()->Status;
@@ -109,7 +109,7 @@ public:
                     TLogoBlobID::MaxChannel, TLogoBlobID::MaxBlobSize, TLogoBlobID::MaxCookie),
                     disks, false);
 
-            SendToBSProxy(GetActorContext(), Info->GroupID, new TEvBlobStorage::TEvDiscover(tabletId, 0, true, true, TInstant::Max(), 0));
+            SendToBSProxy(GetActorContext(), Info->GroupID, new TEvBlobStorage::TEvDiscover(tabletId, 0, true, true, TInstant::Max(), 0, true));
             auto response = WaitForSpecificEvent<TEvBlobStorage::TEvDiscoverResult>();
 
             UNIT_ASSERT_VALUES_EQUAL(response->Get()->Status, NKikimrProto::OK);
diff --git a/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp b/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
index fdd7a92ea3..dcb316ec9c 100644
--- a/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
@@ -1277,7 +1277,7 @@ Y_UNIT_TEST(TestGivenBlock42Put6PartsOnOneVDiskWhenDiscoverThenRecoverFirst) {
     const ui32 minGeneration = 0;
     // Send Discover
     runtime.Send(new IEventHandle(
-        proxy, sender, new TEvBlobStorage::TEvDiscover(tabletId, minGeneration, true, false, TInstant::Max(), 0)));
+        proxy, sender, new TEvBlobStorage::TEvDiscover(tabletId, minGeneration, true, false, TInstant::Max(), 0, true)));
 
     // Receive VGet
     TMap<TActorId, TGetRequest> lastRequest;
diff --git a/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp b/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
index b77d654677..7679f57102 100644
--- a/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
@@ -964,7 +964,7 @@ class TTestBlobStorageProxyBlock : public TTestBlobStorageProxy {
                 TEST_RESPONSE(MessagePutResult, BLOCKED, 0, "");
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 80:
             {
@@ -2334,13 +2334,13 @@ class TTestBlobStorageProxySimpleDiscover : public TTestBlobStorageProxy {
                 TEST_RESPONSE(MessagePutResult, OK, 0, "");
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 30:
                 TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 40:
                 TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
@@ -2372,7 +2372,7 @@ class TTestBlobStorageProxyDiscover : public TTestBlobStorageProxy {
                     "Unexpected " << (int)LastResponse.Message);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 10:
                 UNIT_ASSERT_EQUAL_C(LastResponse.Message, TResponseData::MessageDiscoverResult,
@@ -2380,7 +2380,7 @@ class TTestBlobStorageProxyDiscover : public TTestBlobStorageProxy {
 
                 if (LastResponse.Status != NKikimrProto::OK) {
                     VERBOSE_COUT("ReSending TEvDiscover (due to " << (int)LastResponse.Status << ")");
-                    ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                    ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                     TestStep -= 10;
                     break;
                 }
@@ -2388,14 +2388,14 @@ class TTestBlobStorageProxyDiscover : public TTestBlobStorageProxy {
                 TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 20:
                 UNIT_ASSERT_EQUAL_C(LastResponse.Message, TResponseData::MessageDiscoverResult,
                         "Unexpected message type# " << (int)LastResponse.Message);
                 if (LastResponse.Status != NKikimrProto::OK) {
                     VERBOSE_COUT("ReSending TEvDiscover (due to " << (int)LastResponse.Status << ")");
-                    ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                    ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                     TestStep -= 10;
                     break;
                 }
@@ -2426,13 +2426,13 @@ class TTestBlobStorageProxyDiscoverFail : public TTestBlobStorageProxy {
                     "Unexpected " << (int)LastResponse.Message);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 10:
                 TEST_RESPONSE(MessageDiscoverResult, ERROR, 0, "");
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 20:
                 TEST_RESPONSE(MessageDiscoverResult, ERROR, 0, "");
@@ -2462,13 +2462,13 @@ class TTestBlobStorageProxyDiscoverEmpty : public TTestBlobStorageProxy {
                     "Unexpected " << (int)LastResponse.Message);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 10:
                 TEST_RESPONSE(MessageDiscoverResult, NODATA, 0, "");
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 20:
                 TEST_RESPONSE(MessageDiscoverResult, NODATA, 0, "");
@@ -2498,13 +2498,13 @@ class TTestBlobStorageProxyDiscoverTimeout : public TTestBlobStorageProxy {
                     "Unexpected " << (int)LastResponse.Message);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 10:
                 TEST_RESPONSE(MessageDiscoverResult, TIMEOUT, 0, "");
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 20:
                 TEST_RESPONSE(MessageDiscoverResult, TIMEOUT, 0, "");
@@ -2693,14 +2693,14 @@ class TTestBlobStorageProxyLongTailDiscover : public TTestBlobStorageProxy {
                     "Unexpected " << (int)LastResponse.Message);
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 10:
                 TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
 
 
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 20:
                 TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
@@ -3056,7 +3056,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessagePutResult, OK, 0, "");
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 230:
                 if (Env->ShouldBeUndiscoverable) {
@@ -3065,7 +3065,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = false, expecting OK");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, false, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, false, false, TInstant::Max(), 0, true));
                 break;
             case 240:
                 if (Env->ShouldBeUndiscoverable) {
@@ -3074,7 +3074,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessageDiscoverResult, OK, 1, "");
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting NODATA");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(2/*tabletId*/, 0, true, false, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(2/*tabletId*/, 0, true, false, TInstant::Max(), 0, true));
                 break;
             case 250:
                 if (Env->ShouldBeUndiscoverable) {
@@ -3083,7 +3083,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessageDiscoverResult, NODATA, 0, "");
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting OK + data");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 260:
                 if (Env->ShouldBeUndiscoverable) {
@@ -3092,7 +3092,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessageDiscoverResult, OK, 1, testData2);
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = false, expecting OK");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, false, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(1, 0, false, true, TInstant::Max(), 0, true));
                 break;
             case 270:
                 if (Env->ShouldBeUndiscoverable) {
@@ -3101,7 +3101,7 @@ class TTestBlobStorageProxyBasic1 : public TTestBlobStorageProxy {
                     TEST_RESPONSE(MessageDiscoverResult, OK, 1, "");
                 }
                 VERBOSE_COUT("Sending TEvDiscover, read body = true, expecting NODATA");
-                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(2/*tabletId*/, 0, true, true, TInstant::Max(), 0));
+                ctx.Send(Proxy, new TEvBlobStorage::TEvDiscover(2/*tabletId*/, 0, true, true, TInstant::Max(), 0, true));
                 break;
             case 280:
             {
diff --git a/ydb/core/blobstorage/testload/test_load_write.cpp b/ydb/core/blobstorage/testload/test_load_write.cpp
index 3169c1609e..d30f9d4a31 100644
--- a/ydb/core/blobstorage/testload/test_load_write.cpp
+++ b/ydb/core/blobstorage/testload/test_load_write.cpp
@@ -249,7 +249,7 @@ class TLogWriterTestLoadActor : public TActorBootstrapped<TLogWriterTestLoadActo
         // Issue TEvDiscover
         void Bootstrap(const TActorContext& ctx) {
             NextWriteTimestamp = TAppData::TimeProvider->Now();
-            auto ev = std::make_unique<TEvBlobStorage::TEvDiscover>(TabletId, Generation, false, true, TInstant::Max(), 0);
+            auto ev = std::make_unique<TEvBlobStorage::TEvDiscover>(TabletId, Generation, false, true, TInstant::Max(), 0, true);
             LOG_DEBUG_S(ctx, NKikimrServices::BS_LOAD_TEST, PrintMe() << " is bootstrapped, going to send "
                     << ev->ToString());
             auto callback = [this] (IEventBase *event, const TActorContext& ctx) {
diff --git a/ydb/core/blobstorage/ut_blobstorage/lib/activity.h b/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
index 478a87b707..8c6f3bfd48 100644
--- a/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
+++ b/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
@@ -75,7 +75,7 @@ public:
     }
 
     void IssueDiscover() {
-        SendToProxy(TDuration::MilliSeconds(100), new TEvBlobStorage::TEvDiscover(TabletId, 0, false, false, TInstant::Max(), 0));
+        SendToProxy(TDuration::MilliSeconds(100), new TEvBlobStorage::TEvDiscover(TabletId, 0, false, false, TInstant::Max(), 0, true));
     }
 
     void Handle(TEvBlobStorage::TEvDiscoverResult::TPtr ev) {
diff --git a/ydb/core/blobstorage/ut_group/main.cpp b/ydb/core/blobstorage/ut_group/main.cpp
index 538f46ae03..12b8ab5114 100644
--- a/ydb/core/blobstorage/ut_group/main.cpp
+++ b/ydb/core/blobstorage/ut_group/main.cpp
@@ -490,7 +490,7 @@ public:
         }
 
         // discover previously written data
-        if (auto ev = Query<TEvBlobStorage::TEvDiscover>(TabletId, 0, true, false, TInstant::Max(), 0)) {
+        if (auto ev = Query<TEvBlobStorage::TEvDiscover>(TabletId, 0, true, false, TInstant::Max(), 0, true)) {
             Y_VERIFY(ev->Get()->Status == (Committed.empty() ? NKikimrProto::NODATA : NKikimrProto::OK));
             if (ev->Get()->Status == NKikimrProto::OK) {
                 Y_VERIFY(ev->Get()->Buffer == Committed.rbegin()->second);
diff --git a/ydb/core/tablet/tablet_impl.h b/ydb/core/tablet/tablet_impl.h
index b47b1f1097..4a4a2bb784 100644
--- a/ydb/core/tablet/tablet_impl.h
+++ b/ydb/core/tablet/tablet_impl.h
@@ -14,7 +14,7 @@
 namespace NKikimr {
 
 IActor* CreateTabletReqRebuildHistoryGraph(const TActorId &owner, TTabletStorageInfo *info, ui32 blockedGen, NTracing::ITrace *trace, ui64 followerCookie);
-IActor* CreateTabletFindLastEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGen);
+IActor* CreateTabletFindLastEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGen, bool leader);
 IActor* CreateTabletReqWriteLog(const TActorId &owner, const TLogoBlobID &entryId, NKikimrTabletBase::TTabletLogEntry *entry, TVector<TEvTablet::TLogEntryReference> &refs, TEvBlobStorage::TEvPut::ETactic commitTactic, TTabletStorageInfo *info);
 IActor* CreateTabletReqBlockBlobStorage(const TActorId &owner, TTabletStorageInfo *info, ui32 generation, bool blockPrevEntry);
 IActor* CreateTabletReqDelete(const TActorId &owner, const TIntrusivePtr<TTabletStorageInfo> &tabletStorageInfo, ui32 generation = std::numeric_limits<ui32>::max());
diff --git a/ydb/core/tablet/tablet_req_findlatest.cpp b/ydb/core/tablet/tablet_req_findlatest.cpp
index ca3d09aa43..59f6b5af36 100644
--- a/ydb/core/tablet/tablet_req_findlatest.cpp
+++ b/ydb/core/tablet/tablet_req_findlatest.cpp
@@ -17,6 +17,7 @@ class TTabletReqFindLatestLogEntry : public TActorBootstrapped<TTabletReqFindLat
     const TActorId Owner;
     const bool ReadBody;
     const ui32 BlockedGeneration;
+    const bool Leader;
     TIntrusivePtr<TTabletStorageInfo> Info;
     const TTabletChannelInfo *ChannelInfo;
     ui64 CurrentHistoryIndex;
@@ -33,7 +34,7 @@ class TTabletReqFindLatestLogEntry : public TActorBootstrapped<TTabletReqFindLat
 
         const ui32 group = ChannelInfo->History[CurrentHistoryIndex].GroupID;
         const ui32 minGeneration = ChannelInfo->History[CurrentHistoryIndex].FromGeneration;
-        auto request = MakeHolder<TEvBlobStorage::TEvDiscover>(Info->TabletID, minGeneration, ReadBody, true, TInstant::Max(), BlockedGeneration);
+        auto request = MakeHolder<TEvBlobStorage::TEvDiscover>(Info->TabletID, minGeneration, ReadBody, true, TInstant::Max(), BlockedGeneration, Leader);
         SendToBSProxy(SelfId(), group, request.Release());
     }
 
@@ -72,10 +73,11 @@ public:
         return NKikimrServices::TActivity::TABLET_REQ_FIND_LATEST;
     }
 
-    TTabletReqFindLatestLogEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGeneration)
+    TTabletReqFindLatestLogEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGeneration, bool leader)
         : Owner(owner)
         , ReadBody(readBody)
         , BlockedGeneration(blockedGeneration)
+        , Leader(leader)
         , Info(info)
         , ChannelInfo(Info->ChannelInfo(0))
         , CurrentHistoryIndex(ChannelInfo->History.size())
@@ -96,8 +98,8 @@ public:
     }
 };
 
-IActor* CreateTabletFindLastEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGeneration) {
-    return new TTabletReqFindLatestLogEntry(owner, readBody, info, blockedGeneration);
+IActor* CreateTabletFindLastEntry(const TActorId &owner, bool readBody, TTabletStorageInfo *info, ui32 blockedGeneration, bool leader) {
+    return new TTabletReqFindLatestLogEntry(owner, readBody, info, blockedGeneration, leader);
 }
 
 }
diff --git a/ydb/core/tablet/tablet_req_rebuildhistory.cpp b/ydb/core/tablet/tablet_req_rebuildhistory.cpp
index 620b25c1a8..c12f6c93ad 100644
--- a/ydb/core/tablet/tablet_req_rebuildhistory.cpp
+++ b/ydb/core/tablet/tablet_req_rebuildhistory.cpp
@@ -890,9 +890,9 @@ public:
         }
 
         if (FollowerCookie == 0)
-            Register(CreateTabletFindLastEntry(SelfId(), true, Info.Get(), BlockedGen));
+            Register(CreateTabletFindLastEntry(SelfId(), true, Info.Get(), BlockedGen, true));
         else
-            Register(CreateTabletFindLastEntry(SelfId(), true, Info.Get(), 0));
+            Register(CreateTabletFindLastEntry(SelfId(), true, Info.Get(), 0, false));
 
         Become(&TThis::StateWaitLatestEntry);
     }
diff --git a/ydb/core/tablet/tablet_req_reset.cpp b/ydb/core/tablet/tablet_req_reset.cpp
index b73c68c120..a8cfdd5c1a 100644
--- a/ydb/core/tablet/tablet_req_reset.cpp
+++ b/ydb/core/tablet/tablet_req_reset.cpp
@@ -23,7 +23,7 @@ class TTabletReqReset : public TActorBootstrapped<TTabletReqReset> {
     }
 
     void FindLatestLogEntry(const TActorContext& ctx) {
-        ctx.Register(CreateTabletFindLastEntry(ctx.SelfID, false, TabletStorageInfo.Get(), 0));
+        ctx.Register(CreateTabletFindLastEntry(ctx.SelfID, false, TabletStorageInfo.Get(), 0, true));
         Become(&TTabletReqReset::StateDiscover);
     }
 
diff --git a/ydb/core/tablet/tablet_sys.cpp b/ydb/core/tablet/tablet_sys.cpp
index 4537a4af91..613aac9ff9 100644
--- a/ydb/core/tablet/tablet_sys.cpp
+++ b/ydb/core/tablet/tablet_sys.cpp
@@ -839,7 +839,7 @@ void TTablet::HandleStateStorageInfoLock(TEvStateStorage::TEvInfo::TPtr &ev) {
                     , StateStorageInfo.SignatureSz));
             }
 
-            Register(CreateTabletFindLastEntry(SelfId(), false, Info.Get(), 0));
+            Register(CreateTabletFindLastEntry(SelfId(), false, Info.Get(), 0, Leader));
             Become(&TThis::StateDiscover);
             ReportTabletStateChange(TTabletStateInfo::Discover);
         }