create multiple Redis DB instances based on CONFIG at /etc/sonic/database_config.json (#2182)

this is the first step to moving different databases tables into different database instances

in this PR, only handle multiple database instances creation based on user configuration at /etc/sonic/database_config.json

we keep current method to create single database instance if no extra/new DATABASE configuration exist in database_config.json file.

if user try to configure more db instances at database_config.json , we create those new db instances along with the original db instance existing today.

The configuration is as below, later we can add more db related information if needed:
{
...
"DATABASE": {
"redis-db-01" : {
"port" : "6380",
"database": ["APPL_DB", "STATE_DB"]
},
"redis-db-02" : {
"port" : "6381",
"database":["ASIC_DB"]
},
}
...
}

The detail description is at design doc at Azure/SONiC#271

The main idea is : when database.sh started, we check the configuration and generate corresponding scripts.

rc.local service handle old_config copy when loading new images, there is no dependency between rc.local and database service today, for safety and make sure the copy operation are done before database try to read it, we make database service run after rc.local

Then database docker started, we check the configuration and generate corresponding scripts/.conf in database docker as well.

based on those conf, we create databases instances as required.

at last, we ping_pong check database are up and continue


Signed-off-by: Dong Zhang d.zhang@alibaba-inc.com

dockers/docker-database/Dockerfile.j2

@@ -32,6 +32,9 @@ RUN apt-get clean -y                                  && \
              s/^client-output-buffer-limit pubsub [0-9]+mb [0-9]+mb [0-9]+/client-output-buffer-limit pubsub 0 0 0/ \
             ' /etc/redis/redis.conf
 
-COPY ["supervisord.conf", "/etc/supervisor/conf.d/"]
+COPY ["supervisord.conf.j2", "/usr/share/sonic/templates/"]
+COPY ["docker-database-init.sh", "/usr/local/bin/"]
+COPY ["ping_pong_db_insts", "/usr/local/bin/"]
+COPY ["database_config.json", "/etc/default/sonic-db/"]
 
-ENTRYPOINT ["/usr/bin/supervisord"]
+ENTRYPOINT ["/usr/local/bin/docker-database-init.sh"]

dockers/docker-database/database_config.json

@@ -0,0 +1,43 @@
+{
+    "INSTANCES": {
+        "redis":{
+            "port": 6379,
+            "socket": "/var/run/redis/redis.sock"
+        }
+    },
+    "DATABASES" : {
+        "APPL_DB" : {
+            "id" : 0,
+            "instance" : "redis"
+        },
+        "ASIC_DB" : {
+            "id" : 1,
+            "instance" : "redis"
+        },
+        "COUNTERS_DB" : {
+            "id" : 2,
+            "instance" : "redis"
+        },
+        "LOGLEVEL_DB" : {
+            "id" : 3,
+            "instance" : "redis"
+        },
+        "CONFIG_DB" : {
+            "id" : 4,
+            "instance" : "redis"
+        },
+        "PFC_WD_DB" : {
+            "id" : 5,
+            "instance" : "redis"
+        },
+        "FLEX_COUNTER_DB" : {
+            "id" : 5,
+            "instance" : "redis"
+        },
+        "STATE_DB" : {
+            "id" : 6,
+            "instance" : "redis"
+        }
+    },
+    "VERSION" : "1.0"
+}

dockers/docker-database/docker-database-init.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+
+mkdir -p /var/run/redis/sonic-db
+if [ -f /etc/sonic/database_config.json ]; then
+    cp /etc/sonic/database_config.json /var/run/redis/sonic-db
+else
+    cp /etc/default/sonic-db/database_config.json /var/run/redis/sonic-db
+fi
+
+mkdir -p /etc/supervisor/conf.d/
+# generate all redis server supervisord configuration file
+sonic-cfggen -j /var/run/redis/sonic-db/database_config.json -t /usr/share/sonic/templates/supervisord.conf.j2 > /etc/supervisor/conf.d/supervisord.conf
+
+exec /usr/bin/supervisord

dockers/docker-database/ping_pong_db_insts

@@ -0,0 +1,40 @@
+#!/usr/bin/python
+import json
+import os
+import subprocess
+import time
+import syslog
+
+def ping_redis(cmd):
+    output = ''
+    while True:
+        try:
+            output = subprocess.check_output(cmd, shell=True)
+        except subprocess.CalledProcessError as e:
+            syslog.syslog(syslog.LOG_ERR, 'ping redis failed, cmd : {}'.format(cmd))
+
+        if 'PONG' in output:
+            break
+        syslog.syslog(syslog.LOG_ERR, 'ping response : {}'.format(output))
+        time.sleep(1)
+
+database_config_file = "/var/run/redis/sonic-db/database_config.json"
+
+data = {}
+while True:
+    if os.path.isfile(database_config_file):
+        with open(database_config_file, "r") as read_file:
+            data = json.load(read_file)
+        break
+    time.sleep(1)
+    syslog.syslog(syslog.LOG_ERR, 'config file {} does not exist right now'.format(database_config_file))
+
+while True:
+    if 'INSTANCES' in data:
+        for inst in data["INSTANCES"]:
+            port = data["INSTANCES"][inst]["port"]
+            cmd = "redis-cli -p " + str(port) + " ping"
+            ping_redis(cmd)
+        break
+    time.sleep(1)
+    syslog.syslog(syslog.LOG_ERR, 'config file {} does not have INSTANCES'.format(database_config_file))

dockers/docker-database/supervisord.conf

@@ -1,21 +0,0 @@
-[supervisord]
-logfile_maxbytes=1MB
-logfile_backups=2
-nodaemon=true
-
-[program:rsyslogd]
-command=/bin/bash -c "rm -f /var/run/rsyslogd.pid && /usr/sbin/rsyslogd -n"
-priority=1
-autostart=true
-autorestart=false
-stdout_logfile=syslog
-stderr_logfile=syslog
-
-[program:redis-server]
-command=/bin/bash -c "{ [[ -s /var/lib/redis/dump.rdb ]] || rm -f /var/lib/redis/dump.rdb; } && exec /usr/bin/redis-server /etc/redis/redis.conf"
-priority=2
-autostart=true
-autorestart=false
-stdout_logfile=syslog
-stderr_logfile=syslog
-

dockers/docker-database/supervisord.conf.j2

@@ -0,0 +1,24 @@
+[supervisord]
+logfile_maxbytes=1MB
+logfile_backups=2
+nodaemon=true
+
+[program:rsyslogd]
+command=/bin/bash -c "rm -f /var/run/rsyslogd.pid && /usr/sbin/rsyslogd -n"
+priority=1
+autostart=true
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+
+{% if INSTANCES %}
+{%     for redis_inst, redis_items in INSTANCES.iteritems() %}
+[program: {{ redis_inst }}]
+command=/bin/bash -c "{ [[ -s /var/lib/{{ redis_inst }}/dump.rdb ]] || rm -f /var/lib/{{ redis_inst }}/dump.rdb; } && mkdir -p /var/lib/{{ redis_inst }} && exec /usr/bin/redis-server /etc/redis/redis.conf --port {{ redis_items['port'] }} --unixsocket {{ redis_items['socket'] }} --pidfile /var/run/redis/{{ redis_inst }}.pid --dir /var/lib/{{ redis_inst }}"
+priority=2
+autostart=true
+autorestart=false
+stdout_logfile=syslog
+stderr_logfile=syslog
+{%     endfor %}
+{% endif %}

files/build_templates/database.service.j2

@@ -2,6 +2,7 @@
 Description=Database container
 Requires=docker.service
 After=docker.service
+After=rc-local.service
 
 [Service]
 User=root

files/build_templates/docker_image_ctl.j2

@@ -71,10 +71,7 @@ function postStartAction()
 {
 {%- if docker_container_name == "database" %}
     # Wait until redis starts
-    REDIS_SOCK="/var/run/redis/redis.sock"
-    until [[ $(/usr/bin/docker exec database redis-cli -s $REDIS_SOCK ping | grep -c PONG) -gt 0 ]]; do
-        sleep 1;
-    done
+    /usr/bin/docker exec database ping_pong_db_insts
     if [[ ("$BOOT_TYPE" == "warm" || "$BOOT_TYPE" == "fastfast") && -f $WARM_DIR/dump.rdb ]]; then
         rm -f $WARM_DIR/dump.rdb
     else
@@ -163,6 +160,11 @@ start() {
 
 {%- if docker_container_name == "database" %}
     echo "Creating new {{docker_container_name}} container"
+    # if database_config exists in old_config, use it; otherwise use the default one in new image
+    if [ -f /etc/sonic/old_config/database_config.json ]; then
+        echo "Use database_config.json from old system..."
+        mv /etc/sonic/old_config/database_config.json /etc/sonic/
+    fi
 {%- else %}
     echo "Creating new {{docker_container_name}} container with HWSKU $HWSKU"
 {%- endif %}