diff --git a/docs/references/api.md b/docs/references/api.md
index 1acc157a8..6e870e5c1 100644
--- a/docs/references/api.md
+++ b/docs/references/api.md
@@ -1059,12 +1059,13 @@ This is currently internal API and is documented here for completeness.
 Response(200):
 ```
 {
-  "provider": <string>,  // 'caas'
+  "provider": <string>,  // 'caas' or 's3' or 'filesystem'
   "key": <string>,       // encryption key
   "region": <string>,    // s3 region
   "bucket": <string>,    // s3 bucket name
   "prefix": <string>,    // s3 bucket prefix
-  "token": <string>      // caas specific token
+  "token": <string>,     // 'caas' specific token
+  "backupFolder": <string> // 'filesystem' specific backup directory
 }
 ```
 
diff --git a/src/settings.js b/src/settings.js
index dc80c3a7e..a15ccbea6 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -388,8 +388,13 @@ function setBackupConfig(backupConfig, callback) {
     assert.strictEqual(typeof backupConfig, 'object');
     assert.strictEqual(typeof callback, 'function');
 
-    if (backupConfig.provider !== 'caas') {
-        return callback(new SettingsError(SettingsError.BAD_FIELD, 'provider must be caas'));
+    if (backupConfig.provider === 'caas') {
+        if (config.provider() !== 'caas') return callback(new SettingsError(SettingsError.BAD_FIELD, 'provider must be caas'));
+    } else if (backupConfig.provider === 'filesystem') {
+        if (typeof backupConfig.backupFolder !== 'string') return callback(new SettingsError(SettingsError.BAD_FIELD, 'backupFolder must be string'));
+    } else if (backupConfig.provider === 's3') {
+        if (typeof backupConfig.accessKeyId !== 'string') return callback(new SettingsError(SettingsError.BAD_FIELD, 'accessKeyId must be a string'));
+        if (typeof backupConfig.secretAccessKey !== 'string') return callback(new SettingsError(SettingsError.BAD_FIELD, 'secretAccessKey must be a string'));
     }
 
     settingsdb.set(exports.BACKUP_CONFIG_KEY, JSON.stringify(backupConfig), function (error) {