Implement clock CLI

files/build_templates/init_cfg.json.j2

@@ -4,7 +4,8 @@
             "buffer_model": {% if default_buffer_model == "dynamic" %}"dynamic"{% else %}"traditional"{% endif %},
             {%- if include_p4rt == "y" %}"synchronous_mode":"enable",{% endif %}
             "default_bgp_status": {% if shutdown_bgp_on_start == "y" %}"down"{% else %}"up"{% endif %},
-            "default_pfcwd_status": {% if enable_pfcwd_on_start == "y" %}"enable"{% else %}"disable"{% endif %}
+            "default_pfcwd_status": {% if enable_pfcwd_on_start == "y" %}"enable"{% else %}"disable"{% endif %},
+            "timezone": "Etc/UTC"
         }
     },
     "CRM": {

src/sonic-yang-models/doc/Configuration.md

@@ -865,7 +865,8 @@ instance is supported in SONiC.
         "type": "ToRRouter",
         "bgp_adv_lo_prefix_as_128" : "true",
         "buffer_model": "traditional",
-        "yang_config_validation": "disable"
+        "yang_config_validation": "disable",
+        "timezome": "Europe/Kiev"
     }
   }
 }

src/sonic-yang-models/tests/files/sample_config_db.json

@@ -357,7 +357,8 @@
                 "sub_role": "FrontEnd",
                 "dhcp_server": "disabled",
                 "bgp_adv_lo_prefix_as_128": "true",
-                "yang_config_validation": "disable"
+                "yang_config_validation": "disable",
+                "timezone": "Europe/Kiev"
             }
         },
         "VLAN": {

src/sonic-yang-models/tests/yang_model_tests/tests/device_metadata.json

@@ -125,6 +125,13 @@
     },
     "DEVICE_METADATA_ADVERTISE_LO_PREFIX_AS_128": {
         "desc": "Verifying advertising lo prefix as /128."
+    },
+    "DEVICE_METADATA_VALID_TIMEZONE": {
+        "desc": "Verifying valid timezone value"
+    },
+    "DEVICE_METADATA_INVALID_TIMEZONE": {
+        "desc": "Verifying invalid timezone value",
+        "eStrKey": "Range"
     }
 
 }

src/sonic-yang-models/tests/yang_model_tests/tests_config/device_metadata.json

@@ -332,5 +332,23 @@
                 }
             }
         }
+    },
+    "DEVICE_METADATA_VALID_TIMEZONE": {
+        "sonic-device_metadata:sonic-device_metadata": {
+            "sonic-device_metadata:DEVICE_METADATA": {
+                "sonic-device_metadata:localhost": {
+                    "timezone": "Etc/UTC"
+                }
+            }
+        }
+    },
+    "DEVICE_METADATA_INVALID_TIMEZONE": {
+        "sonic-device_metadata:sonic-device_metadata": {
+            "sonic-device_metadata:DEVICE_METADATA": {
+                "sonic-device_metadata:localhost": {
+                    "timezone": ""
+                }
+            }
+        }
     }
 }

src/sonic-yang-models/yang-models/sonic-device_metadata.yang

@@ -204,6 +204,15 @@ module sonic-device_metadata {
                     description "Advertise Loopback0 interface IPv6 /128 subnet address as it is with set to true.
                                  By default SONiC advertises /128 subnet prefix in Loopback0 as /64 subnet route";
                 }
+
+                leaf timezone {
+                    type stypes:timezone-name-type {
+                        length 1..255;
+                    }
+                    default "Etc/UTC";
+                    description "The TZ database name to use for the system, such as 'Europe/Stockholm'.";
+                    reference "IANA Time Zone Database http://www.iana.org/time-zones";
+                }
             }
             /* end of container localhost */
         }

src/sonic-yang-models/yang-templates/sonic-types.yang.j2

@@ -333,6 +333,19 @@ module sonic-types {
         }
     }
 
+    typedef timezone-name-type {
+        type string;
+        description
+            "A time zone name as used by the Time Zone Database,
+            sometimes referred to as the 'Olson Database'.
+
+            The exact set of valid values is an implementation-specific
+            matter.  Client discovery of the exact set of time zone names
+            for a particular server is out of scope.";
+        reference
+            "BCP 175: Procedures for Maintaining the Time Zone Database";
+    }
+
     {% if yang_model_type == "cvl" %}
     /* Required for CVL */
     container operation {