[multiDB] add database_config.json into vs images (#3757)

platform/vs/docker-sonic-vs/Dockerfile.j2

@@ -106,6 +106,7 @@ COPY ["files/configdb-load.sh", "/usr/bin/"]
 COPY ["files/arp_update", "/usr/bin/"]
 COPY ["files/buffers_config.j2", "files/qos_config.j2", "/usr/share/sonic/templates/"]
 COPY ["files/sonic_version.yml", "/etc/sonic/"]
+COPY ["database_config.json", "/etc/default/sonic-db/"]
 
 # Workaround the tcpdump issue
 RUN mv /usr/sbin/tcpdump /usr/bin/tcpdump

platform/vs/docker-sonic-vs/database_config.json

@@ -0,0 +1,57 @@
+{
+    "INSTANCES": {
+        "redis":{
+            "hostname" : "127.0.0.1",
+            "port" : 6379,
+            "unix_socket_path" : "/var/run/redis/redis.sock"
+        }
+    },
+    "DATABASES" : {
+        "APPL_DB" : {
+            "id" : 0,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "ASIC_DB" : {
+            "id" : 1,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "COUNTERS_DB" : {
+            "id" : 2,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "LOGLEVEL_DB" : {
+            "id" : 3,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "CONFIG_DB" : {
+            "id" : 4,
+            "separator": "|",
+            "instance" : "redis"
+        },
+        "PFC_WD_DB" : {
+            "id" : 5,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "FLEX_COUNTER_DB" : {
+            "id" : 5,
+            "separator": ":",
+            "instance" : "redis"
+        },
+        "STATE_DB" : {
+            "id" : 6,
+            "separator": "|",
+            "instance" : "redis"
+        },
+        "SNMP_OVERLAY_DB" : {
+            "id" : 7,
+            "separator": "|",
+            "instance" : "redis"
+        }
+    },
+    "VERSION" : "1.0"
+}

platform/vs/docker-sonic-vs/start.sh

@@ -29,7 +29,8 @@ rm -f /var/run/rsyslogd.pid
 
 supervisorctl start rsyslogd
 
-mkdir -p /var/run/redis
+mkdir -p /var/run/redis/sonic-db
+cp /etc/default/sonic-db/database_config.json /var/run/redis/sonic-db/
 
 supervisorctl start redis-server