diff --git a/lib/isc/include/isc/log.h b/lib/isc/include/isc/log.h
index d2d2886161..2251a42837 100644
--- a/lib/isc/include/isc/log.h
+++ b/lib/isc/include/isc/log.h
@@ -177,7 +177,8 @@ LIBISC_EXTERNAL_DATA extern isc_logmodule_t isc_modules[];
 #define ISC_LOGMODULE_INTERFACE (&isc_modules[2])
 #define ISC_LOGMODULE_TIMER (&isc_modules[3])
 #define ISC_LOGMODULE_FILE (&isc_modules[4])
-#define ISC_LOGMODULE_OTHER (&isc_modules[5])
+#define ISC_LOGMODULE_NETMGR (&isc_modules[5])
+#define ISC_LOGMODULE_OTHER (&isc_modules[6])
 
 ISC_LANG_BEGINDECLS
 
diff --git a/lib/isc/log.c b/lib/isc/log.c
index 0af599f8c2..3d60ca2fad 100644
--- a/lib/isc/log.c
+++ b/lib/isc/log.c
@@ -192,6 +192,7 @@ LIBISC_EXTERNAL_DATA isc_logmodule_t isc_modules[] = {
 	{ "interface", 0 },
 	{ "timer", 0 },
 	{ "file", 0 },
+	{ "netmgr", 0 },
 	{ "other", 0 },
 	{ NULL, 0 }
 };
diff --git a/lib/isc/netmgr/tcp.c b/lib/isc/netmgr/tcp.c
index c400866db7..56e8600f57 100644
--- a/lib/isc/netmgr/tcp.c
+++ b/lib/isc/netmgr/tcp.c
@@ -15,6 +15,7 @@
 #include <isc/atomic.h>
 #include <isc/buffer.h>
 #include <isc/condition.h>
+#include <isc/log.h>
 #include <isc/magic.h>
 #include <isc/mem.h>
 #include <isc/netmgr.h>
@@ -500,15 +501,19 @@ accept_connection(isc_nmsocket_t *ssock) {
 static void
 tcp_connection_cb(uv_stream_t *server, int status) {
 	isc_nmsocket_t *ssock = server->data;
-	isc_result_t result = accept_connection(ssock);
+	isc_result_t result;
 
 	UNUSED(status);
 
+	result = accept_connection(ssock);
 	if (result != ISC_R_SUCCESS) {
 		if (result == ISC_R_QUOTA || result == ISC_R_SOFTQUOTA) {
 			ssock->overquota = true;
 		}
-		/* TODO: Log the error. */
+		isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
+			      ISC_LOGMODULE_NETMGR, ISC_LOG_ERROR,
+			      "TCP connection failed: %s",
+			      isc_result_totext(result));
 	}
 }