elastic_ L02_ install

Reading guide

The description and explanation of this article are based on ElasticSearch 7.15.1 edition , Installed in the centos7 Environment , If the article configuration is different , Subject to the official website documents , Mainly about downloading 、 install 、 Description of operation and main configuration .

1. download

Official website download address

JVM To configure -config/jvm.options The default setting is 4GB

Configuration suggestions ：Xmx Don't exceed the memory of the machine 50%, Don't exceed 30GB

2. install

Official website installation documents

# Download and install 
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.15.1-linux-x86_64.tar.gz
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.15.1-linux-x86_64.tar.gz.sha512
shasum -a 512 -c elasticsearch-7.15.1-linux-x86_64.tar.gz.sha512 
tar -xzf elasticsearch-7.15.1-linux-x86_64.tar.gz
cd elasticsearch-7.15.1/
#  Install word segmentation plug-in 
./bin/elasticsearch-plugin install  analysis-icu
#  Check the plugin 
./bin/elasticsearch-plugin list

3. function

#  start-up 
./bin/elasticsearch

# verification ES Startup successful   Check the process  
ps -ef|grep es

#  Access port verification ：curl http://127.0.0.1:9200
{
  "name" : "localhost.localdomain",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "_na_",
  "version" : {
    "number" : "7.15.1",
    "build_flavor" : "default",
    "build_type" : "tar",
    "build_hash" : "83c34f456ae29d60e94d886e455e6a3409bba9ed",
    "build_date" : "2021-10-07T21:56:19.031608185Z",
    "build_snapshot" : false,
    "lucene_version" : "8.9.0",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  },
  "tagline" : "You Know, for Search"
}

#  Running multiple instances 
./bin/elasticsearch -d -E cluster.name=my_cluster -Enode.name=node_1

#  Daemons start 
./bin/elasticsearch -d -p pid
#  close 
pkill -F pid

4. problem

problem 1： user

Exception java.lang.RuntimeException: can not run elasticsearch as root

sudo userad es  
sudo passwd es
sudo chown -R es:es  elasticsearch-7.15.1

problem 2： File descriptor

bootstrap check failure [1] of [3]: max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535]

# Additional content ; Log in the user again , Will take effect 
cp /etc/security/limits.conf /etc/security/limits.conf.bak
echo "es soft nofile 65536" >> /etc/security/limits.conf
echo "es hard nofile 65536" >> /etc/security/limits.conf

problem 3： Number of threads

max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]

# Additional content 
cp /etc/sysctl.conf /etc/sysctl.conf.bak
echo "vm.max_map_count=655360" >> /etc/sysctl.conf
sysctl -p

problem 4： Node configuration

the default discovery settings are unsuitable for production use; at least one of [discovery.seed_hosts, discovery.seed_providers, cluster.initial_master_nodes] must be configured

# stay elasticsearch.yml Uncomment keep a node 
cluster.initial_master_nodes: ["node-1"]