diff --git a/drivers/flash/flash_simulator.c b/drivers/flash/flash_simulator.c
index bbc1e6e5af7..c13b0285dd1 100644
--- a/drivers/flash/flash_simulator.c
+++ b/drivers/flash/flash_simulator.c
@@ -438,7 +438,11 @@ static int flash_mock_init(const struct device *dev)
 	struct flash_simulator_data *dev_data = dev->data;
 
 	if (dev_data->flash_in_ram == false && dev_data->flash_file_path == NULL) {
-		dev_data->flash_file_path = cfg->flash_file_default_path;
+		/* ZephCore: default to a per-node file (meshcore_settings_<host>.bin)
+		 * so persistent settings are identifiable and survive restarts.
+		 * cfg->flash_file_default_path ("flash.bin") is the upstream default;
+		 * an explicit --flash=<path> still overrides (flash_file_path != NULL). */
+		dev_data->flash_file_path = flash_mock_default_path_native();
 	}
 
 	rc = flash_mock_init_native(dev_data->flash_in_ram, &dev_data->mock_flash, cfg->flash_size,
diff --git a/drivers/flash/flash_simulator_native.c b/drivers/flash/flash_simulator_native.c
index 03eb8269f58..73249b4fcdd 100644
--- a/drivers/flash/flash_simulator_native.c
+++ b/drivers/flash/flash_simulator_native.c
@@ -28,6 +28,31 @@
 #include <string.h>
 #include <nsi_tracing.h>
 
+/*
+ * ZephCore: build a per-node default flash backing-file name from the host
+ * name, so each node keeps its persistent settings in its own file
+ * (meshcore_settings_<hostname>.bin) rather than a generic flash.bin.
+ * Returns a pointer to a static buffer valid for the process lifetime.
+ */
+const char *flash_mock_default_path_native(void)
+{
+	static char path[128];
+	char host[64];
+
+	if (gethostname(host, sizeof(host)) != 0) {
+		host[0] = '\0';
+	}
+	host[sizeof(host) - 1] = '\0';
+
+	if (host[0] == '\0') {
+		snprintf(path, sizeof(path), "meshcore_settings.bin");
+	} else {
+		snprintf(path, sizeof(path), "meshcore_settings_%s.bin", host);
+	}
+
+	return path;
+}
+
 /*
  * Initialize the flash buffer.
  * And, if the content is to be kept on disk map it to the buffer to the file.
diff --git a/drivers/flash/flash_simulator_native.h b/drivers/flash/flash_simulator_native.h
index a59136c1c20..efc69b7366e 100644
--- a/drivers/flash/flash_simulator_native.h
+++ b/drivers/flash/flash_simulator_native.h
@@ -15,6 +15,9 @@ int flash_mock_init_native(bool flash_in_ram, uint8_t **mock_flash, unsigned int
 			   int *flash_fd, const char *flash_file_path,
 			   unsigned int erase_value, bool flash_erase_at_start);
 
+/* ZephCore: per-node default backing-file path (meshcore_settings_<host>.bin). */
+const char *flash_mock_default_path_native(void);
+
 void flash_mock_cleanup_native(bool flash_in_ram, int flash_fd, uint8_t *mock_flash,
 			       unsigned int size, const char *flash_file_path,
 			       bool flash_rm_at_exit);