diff --git a/conf/nebula-graphd.conf.default b/conf/nebula-graphd.conf.default
index c1be4f72580..a528daa5195 100644
--- a/conf/nebula-graphd.conf.default
+++ b/conf/nebula-graphd.conf.default
@@ -61,6 +61,9 @@
 --num_accept_threads=1
 # The number of networking IO threads, 0 for # of CPU cores
 --num_netio_threads=0
+# Max active connections for all networking threads. 0 means no limit.
+# Max connections for each networking thread = num_max_connections / num_netio_threads
+--num_max_connections=0
 # The number of threads to execute user queries, 0 for # of CPU cores
 --num_worker_threads=0
 # HTTP service ip
diff --git a/conf/nebula-graphd.conf.production b/conf/nebula-graphd.conf.production
index 3f1d828d533..7fd8d3f6da5 100644
--- a/conf/nebula-graphd.conf.production
+++ b/conf/nebula-graphd.conf.production
@@ -60,6 +60,9 @@
 --num_accept_threads=1
 # The number of networking IO threads, 0 for # of CPU cores
 --num_netio_threads=0
+# Max active connections for all networking threads. 0 means no limit.
+# Max connections for each networking thread = num_max_connections / num_netio_threads
+--num_max_connections=0
 # The number of threads to execute user queries, 0 for # of CPU cores
 --num_worker_threads=0
 # HTTP service ip
diff --git a/conf/nebula-storaged.conf.default b/conf/nebula-storaged.conf.default
index 7746aef5057..0d29f5547a6 100644
--- a/conf/nebula-storaged.conf.default
+++ b/conf/nebula-storaged.conf.default
@@ -110,6 +110,9 @@
 --auto_remove_invalid_space=true
 # Network IO threads number
 --num_io_threads=16
+# Max active connections for all networking threads. 0 means no limit.
+# Max connections for each networking thread = num_max_connections / num_netio_threads
+--num_max_connections=0
 # Worker threads number to handle request
 --num_worker_threads=32
 # Maximum subtasks to run admin jobs concurrently
diff --git a/conf/nebula-storaged.conf.production b/conf/nebula-storaged.conf.production
index a5f3f64b92a..f7f42f1093c 100644
--- a/conf/nebula-storaged.conf.production
+++ b/conf/nebula-storaged.conf.production
@@ -111,6 +111,9 @@
 --auto_remove_invalid_space=true
 # Network IO threads number
 --num_io_threads=16
+# Max active connections for all networking threads. 0 means no limit.
+# Max connections for each networking thread = num_max_connections / num_netio_threads
+--num_max_connections=0
 # Worker threads number to handle request
 --num_worker_threads=32
 # Maximum subtasks to run admin jobs concurrently
diff --git a/src/graph/service/GraphFlags.cpp b/src/graph/service/GraphFlags.cpp
index 5b754b1bd89..22f4cbbbcda 100644
--- a/src/graph/service/GraphFlags.cpp
+++ b/src/graph/service/GraphFlags.cpp
@@ -17,6 +17,10 @@ DEFINE_int32(num_netio_threads,
              0,
              "The number of networking threads, 0 for number of physical CPU cores");
 DEFINE_int32(num_accept_threads, 1, "Number of threads to accept incoming connections");
+DEFINE_uint32(num_max_connections,
+              0,
+              "Max active connections for all networking threads. 0 means no limit. Max active "
+              "connections for each networking thread = num_max_connections / num_netio_threads");
 DEFINE_int32(num_worker_threads, 0, "Number of threads to execute user queries");
 DEFINE_int32(num_operator_threads, 2, "Number of threads to execute a single operator");
 DEFINE_bool(reuse_port, true, "Whether to turn on the SO_REUSEPORT option");
diff --git a/src/graph/service/GraphFlags.h b/src/graph/service/GraphFlags.h
index f7a4ecf2416..3ac25c64f11 100644
--- a/src/graph/service/GraphFlags.h
+++ b/src/graph/service/GraphFlags.h
@@ -14,6 +14,7 @@ DECLARE_int32(session_idle_timeout_secs);
 DECLARE_int32(session_reclaim_interval_secs);
 DECLARE_int32(num_netio_threads);
 DECLARE_int32(num_accept_threads);
+DECLARE_uint32(num_max_connections);
 DECLARE_int32(num_worker_threads);
 DECLARE_int32(num_operator_threads);
 DECLARE_bool(reuse_port);
diff --git a/src/graph/service/GraphServer.cpp b/src/graph/service/GraphServer.cpp
index 5073fdb39b8..9f211dae343 100644
--- a/src/graph/service/GraphServer.cpp
+++ b/src/graph/service/GraphServer.cpp
@@ -52,6 +52,7 @@ bool GraphServer::start() {
     thriftServer_->setReusePort(FLAGS_reuse_port);
     thriftServer_->setIdleTimeout(std::chrono::seconds(FLAGS_client_idle_timeout_secs));
     thriftServer_->setNumAcceptThreads(FLAGS_num_accept_threads);
+    thriftServer_->setMaxConnections(FLAGS_num_max_connections);
     thriftServer_->setListenBacklog(FLAGS_listen_backlog);
     if (FLAGS_enable_ssl || FLAGS_enable_graph_ssl) {
       thriftServer_->setSSLConfig(nebula::sslContextConfig());
diff --git a/src/storage/StorageServer.cpp b/src/storage/StorageServer.cpp
index 6bb98f9f76f..10f77f28419 100644
--- a/src/storage/StorageServer.cpp
+++ b/src/storage/StorageServer.cpp
@@ -47,6 +47,10 @@ DECLARE_string(local_ip);
 #endif
 DEFINE_bool(storage_kv_mode, false, "True for kv mode");
 DEFINE_int32(num_io_threads, 16, "Number of IO threads");
+DEFINE_uint32(num_max_connections,
+              0,
+              "Max active connections for all networking threads. 0 means no limit. Max active "
+              "connections for each networking thread = num_max_connections / num_netio_threads");
 DEFINE_int32(storage_http_thread_num, 3, "Number of storage daemon's http thread");
 DEFINE_int32(check_memory_interval_in_secs, 1, "Memory check interval in seconds");
 
@@ -366,6 +370,7 @@ std::unique_ptr<apache::thrift::ThriftServer> StorageServer::getStorageServer()
     server->setIdleTimeout(std::chrono::seconds(0));
     server->setIOThreadPool(ioThreadPool_);
     server->setThreadManager(workers_);
+    server->setMaxConnections(FLAGS_num_max_connections);
     if (FLAGS_enable_ssl) {
       server->setSSLConfig(nebula::sslContextConfig());
     }