diff --git a/src/ckpool.h b/src/ckpool.h
index 0f00e926..12b35a83 100644
--- a/src/ckpool.h
+++ b/src/ckpool.h
@@ -277,6 +277,7 @@ enum stratum_msgtype {
 	SM_WORKINFO,
 	SM_SUGGESTDIFF,
 	SM_BLOCK,
+	SM_PONG,
 	SM_NONE
 };
 
@@ -298,6 +299,7 @@ static const char __maybe_unused *stratum_msgs[] = {
 	"workinfo",
 	"suggestdiff",
 	"block",
+	"pong",
 	""
 };
 
diff --git a/src/connector.c b/src/connector.c
index 7576a8d8..e97d4740 100644
--- a/src/connector.c
+++ b/src/connector.c
@@ -55,7 +55,7 @@ struct client_instance {
 	/* Which serverurl is this instance connected to */
 	int server;
 
-	char buf[PAGESIZE];
+	char *buf;
 	unsigned long bufofs;
 
 	/* Are we currently sending a blocked message from this client */
@@ -205,6 +205,10 @@ static client_instance_t *recruit_client(cdata_t *cdata)
 		client = ckzalloc(sizeof(client_instance_t));
 	} else
 		LOGDEBUG("Connector recycled client instance");
+
+	client->buf = realloc(client->buf, PAGESIZE);
+	client->buf[0] = '\0';
+
 	return client;
 }
 
@@ -457,20 +461,22 @@ static void parse_redirector_share(client_instance_t *client, const json_t *val)
 static void parse_client_msg(cdata_t *cdata, client_instance_t *client)
 {
 	ckpool_t *ckp = cdata->ckp;
-	char msg[PAGESIZE], *eol;
 	int buflen, ret;
+	char *msg, *eol;
 	json_t *val;
 
 retry:
 	if (unlikely(client->bufofs > MAX_MSGSIZE)) {
-		LOGNOTICE("Client id %"PRId64" fd %d overloaded buffer without EOL, disconnecting",
-			  client->id, client->fd);
-		invalidate_client(ckp, cdata, client);
-		return;
+		if (!client->remote) {
+			LOGNOTICE("Client id %"PRId64" fd %d overloaded buffer without EOL, disconnecting",
+				client->id, client->fd);
+			invalidate_client(ckp, cdata, client);
+			return;
+		}
+		client->buf = realloc(client->buf, round_up_page(client->bufofs + MAX_MSGSIZE + 1));
 	}
-	buflen = PAGESIZE - client->bufofs;
 	/* This read call is non-blocking since the socket is set to O_NOBLOCK */
-	ret = read(client->fd, client->buf + client->bufofs, buflen);
+	ret = read(client->fd, client->buf + client->bufofs, MAX_MSGSIZE);
 	if (ret < 1) {
 		if (likely(errno == EAGAIN || errno == EWOULDBLOCK || !ret))
 			return;
@@ -487,12 +493,13 @@ reparse:
 
 	/* Do something useful with this message now */
 	buflen = eol - client->buf + 1;
-	if (unlikely(buflen > MAX_MSGSIZE)) {
+	if (unlikely(buflen > MAX_MSGSIZE && !client->remote)) {
 		LOGNOTICE("Client id %"PRId64" fd %d message oversize, disconnecting", client->id, client->fd);
 		invalidate_client(ckp, cdata, client);
 		return;
 	}
 
+	msg = alloca(round_up_page(buflen + 1));
 	memcpy(msg, client->buf, buflen);
 	msg[buflen] = '\0';
 	client->bufofs -= buflen;
@@ -1009,6 +1016,7 @@ static bool connect_upstream(ckpool_t *ckp, connsock_t *cs)
 	bool res, ret = false;
 	float timeout = 10;
 
+	cksem_wait(&cs->sem);
 	cs->fd = connect_socket(cs->url, cs->port);
 	if (cs->fd < 0) {
 		LOGWARNING("Failed to connect to upstream server %s:%s", cs->url, cs->port);
@@ -1047,6 +1055,8 @@ static bool connect_upstream(ckpool_t *ckp, connsock_t *cs)
 	LOGWARNING("Connected to upstream server %s:%s as trusted remote", cs->url, cs->port);
 	ret = true;
 out:
+	cksem_post(&cs->sem);
+
 	return ret;
 }
 
@@ -1078,10 +1088,92 @@ out:
 	free(buf);
 }
 
+static void parse_remote_submitblock(ckpool_t *ckp, const json_t *val, const char *buf)
+{
+	const char *gbt_block = json_string_value(json_object_get(val, "submitblock"));
+
+	if (unlikely(!gbt_block)) {
+		LOGWARNING("Failed to find submitblock data from upstream submitblock method %s",
+			   buf);
+		return;
+	}
+	LOGWARNING("Submitting possible upstream block!");
+	send_proc(ckp->generator, gbt_block);
+}
+
+static void ping_upstream(cdata_t *cdata)
+{
+	char *buf;
+
+	ASPRINTF(&buf, "{\"method\":\"ping\"}\n");
+	ckmsgq_add(cdata->upstream_sends, buf);
+}
+
+static void *urecv_process(void *arg)
+{
+	ckpool_t *ckp = (ckpool_t *)arg;
+	cdata_t *cdata = ckp->data;
+	connsock_t *cs = &cdata->upstream_cs;
+	bool alive = true;
+
+	ckp->proxy = true;
+
+	rename_proc("ureceiver");
+
+	pthread_detach(pthread_self());
+
+	while (42) {
+		const char *method;
+		float timeout = 5;
+		json_t *val;
+		int ret;
+
+		cksem_wait(&cs->sem);
+		ret = read_socket_line(cs, &timeout);
+		if (ret < 1) {
+			ping_upstream(cdata);
+			if (likely(!ret)) {
+				LOGDEBUG("No message from upstream pool");
+			} else {
+				LOGNOTICE("Failed to read from upstream pool");
+				alive = false;
+			}
+			goto nomsg;
+		}
+		alive = true;
+		val = json_loads(cs->buf, 0, NULL);
+		if (unlikely(!val)) {
+			LOGWARNING("Received non-json msg from upstream pool %s",
+				   cs->buf);
+			goto nomsg;
+		}
+		method = json_string_value(json_object_get(val, "method"));
+		if (unlikely(!method)) {
+			LOGWARNING("Failed to find method from upstream pool json %s",
+				   cs->buf);
+			json_decref(val);
+			goto nomsg;
+		}
+		if (!safecmp(method, "submitblock"))
+			parse_remote_submitblock(ckp, val, cs->buf);
+		else if (!safecmp(method, "pong"))
+			LOGDEBUG("Received upstream pong");
+		else
+			LOGWARNING("Unrecognised upstream method %s", method);
+nomsg:
+		cksem_post(&cs->sem);
+
+		if (!alive)
+			sleep(5);
+	}
+	return NULL;
+}
+
 static bool setup_upstream(ckpool_t *ckp, cdata_t *cdata)
 {
 	connsock_t *cs = &cdata->upstream_cs;
 	bool ret = false;
+	pthread_t pth;
 
 	cs->ckp = ckp;
 	if (!ckp->upstream) {
@@ -1093,11 +1185,14 @@ static bool setup_upstream(ckpool_t *ckp, cdata_t *cdata)
 		goto out;
 	}
 
+	cksem_init(&cs->sem);
+	cksem_post(&cs->sem);
 	/* Must succeed on initial connect to upstream pool */
 	if (!connect_upstream(ckp, cs)) {
 		LOGEMERG("Failed initial connect to upstream server %s:%s", cs->url, cs->port);
 		goto out;
 	}
+	create_pthread(&pth, urecv_process, ckp);
 	cdata->upstream_sends = create_ckmsgq(ckp, "usender", &usend_process);
 	ret = true;
 out:
@@ -1139,7 +1234,7 @@ static void drop_passthrough_client(cdata_t *cdata, const int64_t id)
 	client_id = id & 0xffffffffll;
 	/* We have a direct connection to the passthrough's connector so we
 	 * can send it any regular commands. */
-	ASPRINTF(&msg, "dropclient=%"PRId64, client_id);
+	ASPRINTF(&msg, "dropclient=%"PRId64"\n", client_id);
 	send_client(cdata, id, msg);
 }
 
diff --git a/src/stratifier.c b/src/stratifier.c
index edd8b5b9..ae482593 100644
--- a/src/stratifier.c
+++ b/src/stratifier.c
@@ -472,6 +472,7 @@ struct stratifier_data {
 	stratum_instance_t *stratum_instances;
 	stratum_instance_t *recycled_instances;
 	stratum_instance_t *node_instances;
+	stratum_instance_t *remote_instances;
 
 	int stratum_generated;
 	int disconnected_generated;
@@ -1378,6 +1379,56 @@ static void send_node_block(sdata_t *sdata, const char *enonce1, const char *non
 	}
 }
 
+static void upstream_blocksubmit(ckpool_t *ckp, const char *gbt_block)
+{
+	char *buf;
+
+	ASPRINTF(&buf, "upstream={\"method\":\"submitblock\",\"submitblock\":\"%s\"}\n",
+		 gbt_block);
+	send_proc(ckp->connector, buf);
+	free(buf);
+}
+
+static void downstream_blocksubmits(ckpool_t *ckp, const char *gbt_block, const stratum_instance_t *source)
+{
+	stratum_instance_t *client;
+	sdata_t *sdata = ckp->data;
+	ckmsg_t *bulk_send = NULL;
+	int messages = 0;
+
+	ck_rlock(&sdata->instance_lock);
+	if (sdata->remote_instances) {
+		json_t *val = json_object();
+
+		JSON_CPACK(val, "{ss,ss}",
+			        "method", "submitblock",
+				"submitblock", gbt_block);
+		DL_FOREACH(sdata->remote_instances, client) {
+			ckmsg_t *client_msg;
+			smsg_t *msg;
+			json_t *json_msg;
+
+			if (client == source)
+				continue;
+			json_msg = json_copy(val);
+			client_msg = ckalloc(sizeof(ckmsg_t));
+			msg = ckzalloc(sizeof(smsg_t));
+			msg->json_msg = json_msg;
+			msg->client_id = client->id;
+			client_msg->data = msg;
+			DL_APPEND(bulk_send, client_msg);
+			messages++;
+		}
+		json_decref(val);
+	}
+	ck_runlock(&sdata->instance_lock);
+
+	if (bulk_send) {
+		LOGNOTICE("Sending submitblock to downstream servers");
+		ssend_bulk_prepend(sdata, bulk_send, messages);
+	}
+}
+
 static void
 process_block(ckpool_t *ckp, const workbase_t *wb, const char *coinbase, const int cblen,
 	      const uchar *data, const uchar *hash, uchar *swap32, char *blockhash)
@@ -1414,9 +1465,11 @@ process_block(ckpool_t *ckp, const workbase_t *wb, const char *coinbase, const i
 	if (wb->transactions)
 		realloc_strcat(&gbt_block, wb->txn_data);
 	send_generator(ckp, gbt_block, GEN_PRIORITY);
+	if (ckp->remote)
+		upstream_blocksubmit(ckp, gbt_block);
+	else
+		downstream_blocksubmits(ckp, gbt_block, NULL);
 	free(gbt_block);
-
-
 }
 
 static void submit_node_block(ckpool_t *ckp, sdata_t *sdata, json_t *val)
@@ -2444,6 +2497,8 @@ static void __drop_client(sdata_t *sdata, stratum_instance_t *client, bool lazil
 
 	if (unlikely(client->node))
 		DL_DELETE(sdata->node_instances, client);
+	if (unlikely(client->remote))
+		DL_DELETE(sdata->remote_instances, client);
 	if (client->workername) {
 		if (user) {
 			ASPRINTF(msg, "Dropped client %"PRId64" %s %suser %s worker %s %s",
@@ -2602,11 +2657,6 @@ static void stratum_broadcast(sdata_t *sdata, json_t *val, const int msg_type)
 		return;
 	}
 
-	if (ckp->node) {
-		json_decref(val);
-		return;
-	}
-
 	/* Use this locking as an opportunity to test other clients. */
 	ck_rlock(&ckp_sdata->instance_lock);
 	HASH_ITER(hh, ckp_sdata->stratum_instances, client, tmp) {
@@ -2892,8 +2942,9 @@ static void block_solve(ckpool_t *ckp, const char *blockhash)
 	}
 	mutex_unlock(&sdata->block_lock);
 
-	if (unlikely(!found)) {
-		LOGERR("Failed to find blockhash %s in block_solve!", blockhash);
+	if (!found) {
+		LOGINFO("Failed to find blockhash %s in block_solve, possibly from downstream",
+			blockhash);
 		return;
 	}
 
@@ -2971,8 +3022,9 @@ static void block_reject(sdata_t *sdata, const char *blockhash)
 	}
 	mutex_unlock(&sdata->block_lock);
 
-	if (unlikely(!found)) {
-		LOGERR("Failed to find blockhash %s in block_reject!", blockhash);
+	if (!found) {
+		LOGINFO("Failed to find blockhash %s in block_reject, possibly from downstream",
+			blockhash);
 		return;
 	}
 	val = found->data;
@@ -5539,9 +5591,8 @@ static void add_mining_node(ckpool_t *ckp, sdata_t *sdata, stratum_instance_t *c
 {
 	pthread_t pth;
 
-	client->node = true;
-
 	ck_wlock(&sdata->instance_lock);
+	client->node = true;
 	DL_APPEND(sdata->node_instances, client);
 	__inc_instance_ref(client);
 	ck_wunlock(&sdata->instance_lock);
@@ -5552,6 +5603,14 @@ static void add_mining_node(ckpool_t *ckp, sdata_t *sdata, stratum_instance_t *c
 	create_pthread(&pth, set_node_latency, client);
 }
 
+static void add_remote_server(sdata_t *sdata, stratum_instance_t *client)
+{
+	ck_wlock(&sdata->instance_lock);
+	client->remote = true;
+	DL_APPEND(sdata->remote_instances, client);
+	ck_wunlock(&sdata->instance_lock);
+}
+
 /* Enter with client holding ref count */
 static void parse_method(ckpool_t *ckp, sdata_t *sdata, stratum_instance_t *client,
 			 const int64_t client_id, json_t *id_val, json_t *method_val,
@@ -5610,10 +5669,10 @@ static void parse_method(ckpool_t *ckp, sdata_t *sdata, stratum_instance_t *clie
 				  client_id, client->address, client->server);
 			connector_drop_client(ckp, client_id);
 		} else {
+			add_remote_server(sdata, client);
 			snprintf(buf, 255, "remote=%"PRId64, client_id);
 			send_proc(ckp->connector, buf);
 		}
-		client->remote = true;
 		return;
 	}
 
@@ -5893,6 +5952,23 @@ static void parse_remote_workers(sdata_t *sdata, json_t *val, const char *buf)
 	LOGDEBUG("Adding %d remote workers to user %s", workers, username);
 }
 
+static void parse_remote_blocksubmit(ckpool_t *ckp, json_t *val, const char *buf,
+				     const stratum_instance_t *client)
+{
+	json_t *submitblock_val;
+	const char *gbt_block;
+
+	submitblock_val = json_object_get(val, "submitblock");
+	gbt_block = json_string_value(submitblock_val);
+	if (unlikely(!gbt_block)) {
+		LOGWARNING("Failed to get submitblock data from remote message %s", buf);
+		return;
+	}
+	LOGWARNING("Submitting possible downstream block!");
+	send_generator(ckp, gbt_block, GEN_PRIORITY);
+	downstream_blocksubmits(ckp, gbt_block, client);
+}
+
 static void parse_remote_block(sdata_t *sdata, json_t *val, const char *buf)
 {
 	json_t *workername_val = json_object_get(val, "workername"),
@@ -5923,7 +5999,16 @@ static void parse_remote_block(sdata_t *sdata, json_t *val, const char *buf)
 	reset_bestshares(sdata);
 }
 
-static void parse_trusted_msg(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf)
+static void send_remote_pong(sdata_t *sdata, stratum_instance_t *client)
+{
+	json_t *json_msg;
+
+	JSON_CPACK(json_msg, "{ss}", "method", "pong");
+	stratum_add_send(sdata, json_msg, client->id, SM_PONG);
+}
+
+static void parse_trusted_msg(ckpool_t *ckp, sdata_t *sdata, json_t *val, const char *buf,
+			      stratum_instance_t *client)
 {
 	json_t *method_val = json_object_get(val, "method");
 	const char *method;
@@ -5938,8 +6023,12 @@ static void parse_trusted_msg(ckpool_t *ckp, sdata_t *sdata, json_t *val, const
 		parse_remote_shares(ckp, sdata, val, buf);
 	else if (!safecmp(method, "workers"))
 		parse_remote_workers(sdata, val, buf);
+	else if (!safecmp(method, "submitblock"))
+		parse_remote_blocksubmit(ckp, val, buf, client);
 	else if (!safecmp(method, "block"))
 		parse_remote_block(sdata, val, buf);
+	else if (!safecmp(method, "ping"))
+		send_remote_pong(sdata, client);
 	else
 		LOGWARNING("unrecognised trusted message %s", buf);
 }
@@ -6135,7 +6224,7 @@ static void srecv_process(ckpool_t *ckp, char *buf)
 		LOGINFO("Stratifier added instance %"PRId64" server %d", client->id, server);
 
 	if (client->remote)
-		parse_trusted_msg(ckp, sdata, msg->json_msg, buf);
+		parse_trusted_msg(ckp, sdata, msg->json_msg, buf, client);
 	else if (ckp->node)
 		node_client_msg(ckp, msg->json_msg, buf, client);
 	else