Cleanup agents from DR on REMOVE_HOST cms action

cloud/blockstore/config/storage.proto

@@ -1000,4 +1000,8 @@ message TStorageServiceConfig
 
     // Allow destruction only for those disks whose id matches one of the given prefixes.
     repeated string DestructionAllowedOnlyForDisksWithIdPrefixes = 374;
+
+    // CMS actions such as "REMOVE_HOST" and "REMOVE_DEVICE" will attempt to
+    // remove devices and the host from DR memory (including persistent storage).
+    optional bool CleanupDRConfigOnCMSActions = 375;
 }

cloud/blockstore/libs/storage/core/config.cpp

@@ -419,6 +419,7 @@ TDuration MSeconds(ui32 value)
     xxx(MaxLocalVolumes,                           ui32,      100             )\
                                                                                \
     xxx(DiskRegistryVolumeConfigUpdatePeriod,      TDuration, Minutes(5)      )\
+    xxx(CleanupDRConfigOnCMSActions,               bool,      false           )\
                                                                                \
     xxx(ReassignRequestRetryTimeout,               TDuration, Seconds(5)      )\
     xxx(ReassignChannelsPercentageThreshold,       ui32,      10              )\

cloud/blockstore/libs/storage/core/config.h

@@ -453,6 +453,7 @@ class TStorageConfig
     ui32 GetMaxLocalVolumes() const;
 
     TDuration GetDiskRegistryVolumeConfigUpdatePeriod() const;
+    bool GetCleanupDRConfigOnCMSActions() const;
     TDuration GetReassignRequestRetryTimeout() const;
     ui32 GetReassignChannelsPercentageThreshold() const;
 

cloud/blockstore/libs/storage/core/pending_request.h

@@ -3,6 +3,8 @@
 #include <cloud/blockstore/libs/kikimr/public.h>
 #include <cloud/blockstore/libs/storage/core/request_info.h>
 
+#include <utility>
+
 namespace NCloud::NBlockStore::NStorage {
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -16,7 +18,7 @@ struct TPendingRequest
 
     TPendingRequest(NActors::IEventHandlePtr event, TRequestInfoPtr requestInfo)
         : Event(std::move(event))
-        , RequestInfo(requestInfo)
+        , RequestInfo(std::move(requestInfo))
     {}
 };
 

cloud/blockstore/libs/storage/disk_common/monitoring_utils.cpp

@@ -6,21 +6,34 @@ namespace NCloud::NBlockStore::NStorage {
 
 IOutputStream& DumpAgentState(
     IOutputStream& out,
-    NProto::EAgentState state)
+    NProto::EAgentState state,
+    bool connected)
 {
     switch (state) {
         case NProto::AGENT_STATE_ONLINE:
-            return out << "<font color=green>online</font>";
+            out << "<font color=green>online</font>";
+            break;
         case NProto::AGENT_STATE_WARNING:
-            return out << "<font color=brown>warning</font>";
+            out << "<font color=brown>warning</font>";
+            break;
         case NProto::AGENT_STATE_UNAVAILABLE:
-            return out << "<font color=red>unavailable</font>";
+            out << "<font color=red>unavailable</font>";
+            break;
         default:
-            return out
-                << "(Unknown EAgentState value "
-                << static_cast<int>(state)
+            out << "(Unknown EAgentState value " << static_cast<int>(state)
                 << ")";
+            break;
+    }
+
+    if (state != NProto::AGENT_STATE_UNAVAILABLE) {
+        if (!connected) {
+            out << " <font color=gray>disconnected</font>";
+        }
+    } else if (connected) {
+        out << " <font color=gray>connected</font>";
     }
+
+    return out;
 }
 
 IOutputStream& DumpDiskState(

cloud/blockstore/libs/storage/disk_common/monitoring_utils.h

@@ -32,7 +32,8 @@ inline EDeviceStateFlags& operator|=(EDeviceStateFlags& a, EDeviceStateFlags b)
 
 IOutputStream& DumpAgentState(
     IOutputStream& out,
-    NProto::EAgentState state);
+    NProto::EAgentState state,
+    bool connected);
 
 IOutputStream& DumpDiskState(
     IOutputStream& out,

cloud/blockstore/libs/storage/disk_registry/disk_registry_actor_monitoring.cpp

@@ -517,7 +517,14 @@ void TDiskRegistryActor::RenderAgentHtmlInfo(
             out << "Rack: " << rack;
         }
 
-        DIV() { out << "State: "; DumpAgentState(out, agent->GetState()); }
+        DIV() {
+            out << "State: ";
+
+            auto it = AgentRegInfo.find(agent->GetAgentId());
+            const bool connected =
+                it != AgentRegInfo.end() && it->second.Connected;
+            DumpAgentState(out, agent->GetState(), connected);
+        }
         DIV() {
             out << "State Timestamp: "
                 << TInstant::MicroSeconds(agent->GetStateTs());
@@ -695,7 +702,11 @@ void TDiskRegistryActor::RenderDiskHtmlInfo(
                             != NProto::AGENT_STATE_ONLINE)
                     {
                         out << " ";
-                        DumpAgentState(out, agent->GetState());
+
+                        auto it = AgentRegInfo.find(agent->GetAgentId());
+                        const bool connected =
+                            it != AgentRegInfo.end() && it->second.Connected;
+                        DumpAgentState(out, agent->GetState(), connected);
                     }
                 } else {
                     out << device.GetNodeId();
@@ -1793,22 +1804,10 @@ void TDiskRegistryActor::RenderAgentList(
                             out << config.GetSeqNumber();
                         }
                         TABLED() {
-                            DumpAgentState(out, config.GetState());
-
                             auto it = AgentRegInfo.find(config.GetAgentId());
-
                             const bool connected = it != AgentRegInfo.end()
                                 && it->second.Connected;
-
-                            if (config.GetState()
-                                    != NProto::AGENT_STATE_UNAVAILABLE)
-                            {
-                                if (!connected) {
-                                    out << " <font color=gray>disconnected</font>";
-                                }
-                            } else if (connected) {
-                                out << " <font color=gray>connected</font>";
-                            }
+                            DumpAgentState(out, config.GetState(), connected);
                         }
                         TABLED() {
                             out << (config.GetDedicatedDiskAgent()

cloud/blockstore/libs/storage/disk_registry/disk_registry_state.cpp

@@ -4690,6 +4690,17 @@ NProto::TError TDiskRegistryState::UpdateAgentState(
         return error;
     }
 
+    // Unavailable hosts are a problem when infra tries to request ADD_HOST on
+    // an idle agent. DR waits for it to become online and blocks host
+    // deployment.
+    if (StorageConfig->GetCleanupDRConfigOnCMSActions() &&
+        newState == NProto::AGENT_STATE_UNAVAILABLE &&
+        agent->GetDevices().empty())
+    {
+        RemoveAgent(db, *agent);
+        return {};
+    }
+
     const auto cmsTs = TInstant::MicroSeconds(agent->GetCmsTs());
     const auto oldState = agent->GetState();
     const auto cmsDeadline = cmsTs + GetInfraTimeout(*StorageConfig, oldState);
@@ -5042,6 +5053,20 @@ NProto::TError TDiskRegistryState::UpdateCmsHostState(
     ApplyAgentStateChange(db, *agent, now, affectedDisks);
 
     if (newState != NProto::AGENT_STATE_ONLINE && !HasError(result)) {
+        if (StorageConfig->GetCleanupDRConfigOnCMSActions()) {
+            auto error = TryToRemoveAgentDevices(db, agent->GetAgentId());
+            if (!HasError(error)) {
+                return result;
+            }
+
+            // Do not return the error from "TryToRemoveAgentDevices()" since
+            // it's internal and shouldn't block node removal.
+            STORAGE_WARN(
+                "Could not remove device from agent %s: %s",
+                agent->GetAgentId().Quote().c_str(),
+                FormatError(error).c_str());
+        }
+
         SuspendLocalDevices(db, *agent);
     }
 
@@ -5224,6 +5249,38 @@ bool TDiskRegistryState::TryUpdateDiskState(
     return true;
 }
 
+NProto::TError TDiskRegistryState::TryToRemoveAgentDevices(
+    TDiskRegistryDatabase& db,
+    const TAgentId& agentId)
+{
+    if (!StorageConfig->GetCleanupDRConfigOnCMSActions()) {
+        return MakeError(
+            E_INVALID_STATE,
+            "CleanupDRConfigOnCMSActions is disabled.");
+    }
+
+    auto newConfig = GetConfig();
+    auto* agents = newConfig.MutableKnownAgents();
+    const auto agentIt = FindIf(
+        *agents,
+        [&](const auto& x) { return x.GetAgentId() == agentId; });
+    if (agentIt == agents->end()) {
+        return MakeError(
+            E_NOT_FOUND,
+            TStringBuilder() << "Couldn't find agent " << agentId.Quote()
+                             << " in the DR config.");
+    }
+
+    agents->erase(agentIt);
+    TVector<TString> affectedDisks;
+    auto error = UpdateConfig(
+        db,
+        std::move(newConfig),
+        false,   // ignoreVersion
+        affectedDisks);
+    return error;
+}
+
 void TDiskRegistryState::DeleteDiskStateUpdate(
     TDiskRegistryDatabase& db,
     ui64 maxSeqNo)

cloud/blockstore/libs/storage/disk_registry/disk_registry_state.h

@@ -585,8 +585,8 @@ class TDiskRegistryState
     NProto::TError UpdateAgentState(
         TDiskRegistryDatabase& db,
         const TString& agentId,
-        NProto::EAgentState state,
-        TInstant now,
+        NProto::EAgentState newState,
+        TInstant timestamp,
         TString reason,
         TVector<TDiskId>& affectedDisks);
 
@@ -933,6 +933,10 @@ class TDiskRegistryState
         TDiskState& disk,
         TInstant timestamp);
 
+    NProto::TError TryToRemoveAgentDevices(
+        TDiskRegistryDatabase& db,
+        const TAgentId& agentId);
+
     NProto::TPlacementGroupConfig::TDiskInfo* CollectRacks(
         const TString& diskId,
         ui32 placementPartitionIndex,