Several nouns in Nacos

Nacos is the abbreviation of Dynamic Naming and Configuration Service. A dynamic service discovery, configuration management and service management center that is easier to build cloud native applications.

For Nacos configuration management, you can locate a configuration set through Namespace, Group and Data ID

Configuration set Data ID

In the system, a configuration file is usually a configuration set. A configuration set can contain various configuration information of the system. For example, a configuration set may contain configuration items such as database. Each configuration set can define a meaningful name

Configuration items: configuration items are the configuration contents contained in the configuration set. It represents a specific configurable parameter and its value range, usually in the form of key=value. For example, we often configure the log output level of the system (logLevel=INFO|WARN|ERROR) as a configuration item.

Configure group

Configuration grouping is the grouping of configuration sets, which is identified by a meaningful string. Different configuration groups can have the same configuration set. The default name of the configuration group is DEFAULT_GROUP

Namespace

Namespace can be used for configuration isolation of different environments. Such as isolating development, testing and production environments. Configuration groups or configuration sets (data IDS) with the same name can exist in different namespaces

Nacos installation

Nacos stand alone environment

Download the source code from GitHub

git clone https://github.com/alibaba/nacos.git
cd nacos/
mvn -Prelease-nacos -Dmaven.test.skip=true clean install -U  
ls -al distribution/target/

// change the $version to your actual path
cd distribution/target/nacos-server-$version/nacos/bin

Enter the corresponding version of nacos and execute the command

cd nacos-server-1.2.1/nacos/bin
-- standalone Stand alone mode
sh startup.sh -m standalone

The default port for nacos startup is 8848, the context is / nacos, and the default user name and password is nacos/nacos

You can access the nacos management interface in the browser, such as

http://localhost:8848/nacos

Close nacos server command

sh $Nacos_HOME/bin/shutdown.sh

Nacos cluster construction

Here, three Nacos nodes are used to build the cluster

1. We can copy the extracted nacos folders, named nacos, nacos 1 and nacos 2 respectively

2. Cluster exists in the conf directory of all nacos directories Conf.example and name it cluster Conf and configure the ip:port of each node

127.0.0.1:8848
127.0.0.1:8849
127.0.0.1:8850

3. Start in cluster mode

In each $Nacos_ Execute the command under home / bin

./startup.sh -m cluster

4. After successful startup, nacos can be accessed at any of 127.0.0.1:8848, 127.0.0.1:8849 and 127.0.0.1:8850 nodes

Persistent nacos configuration data

By default, the configuration data in Nacos is stored in the memory based detby database. In order to prevent data loss after server downtime, it is necessary to persist the configuration data to the database.

Nacos supports MySQL database. The specific configuration is as follows:

1. Create a new database. For example, the database name is Nacos, and import the initialization file of the database. The file is $NACOS_HOME/conf/nacos-mysql.sql

2. Modify $NACOS_HOME/conf/application.properties, add mysql database related configuration

### If use MySQL as datasource:
spring.datasource.platform=mysql

### Count of DB:
db.num=1

### Connect URL of DB:
db.url.0=jdbc:mysql://127.0.0.1:3306/nacos?characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true&useUnicode=true&useSSL=false&serverTimezone=UTC
db.user=root
db.password=root

3. Then restart the nacos server

Problems encountered during installation

Problem: after upgrading the mac to bigsur, start.up in nacos SH failed to start. Check start in nacos The following errors are found in the out log:

nohup: /Library/Internet: No such file or directory

Answer: this question is actually related to the mac environment. The mac comes with a jdk. As shown below, there are two. The first is the system's own jdk, and the second is the self installed jdk

/usr/libexec/java_home -v
-- Built in system
java_home: option requires an argument -- v
-- Self installed
/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home

The key to the problem is that the jdk matched by nacos is the system's own, that is, the first one above, and there is a space in its path Internet plug ins, which will cause the shell script to fail. At present, it should be related to bigsur.

The solution is in startup Manually specify your own Java in Sh_ HOME

For example, will

export JAVA_HOME
export JAVA="$JAVA_HOME/bin/java"

Change to

export JAVA_HOME=/Library/Java/JavaVirtualMachines/zulu-8.jdk/Contents/Home
export JAVA="$JAVA_HOME/bin/java"

Then re execute the start command