Elasticsearch profile

Elasticsearch is a distributed, free, open source search and analysis engine for all types of data including text, digital, geospatial, structured and unstructured data, and more. Elasticsearch is a Lucene-based search server. It provides a distributed multi – user – capable full – text search engine based on RESTful Web interface. Elasticsearch, developed in the Java language and released as open source under the Apache license, is a popular enterprise-level search engine. Elasticsearch for cloud computing is stable, reliable, fast, easy to install and use. 【 Details 】

Elasticsearch has been installed

  • Linux CentOS 7.8
  • JDK 11 installation and tutorials

Elasticsearch 7.12.1

Official website download address

Download and unzip:

CD/softwares wget tar at https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.12.1-linux-x86_64.tar.gz - ZXVF elasticsearch 7.12.1 - Linux - x86_64. Tar. GzCopy the code

Create a user and authorize it

# create user elasticUser userAdd elasticUser # set password passwd elasticUser # authorize user elasticUser chow-r Elasticuser /software/ ElasticSearch -7.12.1 chmod -r 777 /software/ ElasticSearch -7.12.1Copy the code

Modify the configuration

Edit config/ elasticSearch. yml, append the content to the end of the file and save it

# = = = = = = = = = = = = = = = = = = = = = = = = Elasticsearch Configuration = = = = = = = = = = = = = = = = = = = = = = = = = # configure Elasticsearch cluster name, Elasticsearch cluster.name: my-elasticsearch cluster.name: my-elasticsearch cluster.name: my-elasticsearch Node-1 #network. Host: 0.0.0.0 #Elasticsearch HTTP access port HTTP. 9200 # This configuration is required to elect master cluster.initial_master_nodes: node-1 when initializing a new clusterCopy the code

Start the Elasticsearch service

Switch to the non-root ES user created above, elasticUser

su elasticuser
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Switch to ElasticSearch -7.12.1/bin and execute

CD/softwares/elasticsearch - 7.12.1 / bin. / elasticsearchCopy the code

If started is displayed, the startup is successful

You can visit http://IP at 9200/

Register the service and set it to boot

vim /usr/lib/systemd/system/elasticsearch.service
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Save the following information

[Unit] Description=elasticsearch After=network.target [Service] Type=forking User=elastic ExecStart=/softwares/ ElasticSearch -7.12.1/bin/ elasticSearch -d PrivateTmp=true # Specifies the maximum number of files this process can open LimitNOFILE=65535 # LimitNPROC=65535 # Maximum virtual memory LimitAS= Infinity # Maximum file size LimitFSIZE= Infinity # Timeout set 0- Never timeout TimeoutStopSec=0 # SIGTERM is the signal to stop the Java process KillSignal=SIGTERM # The signal is only sent to the JVM KillMode=process # The Java process will not be killed SendSIGKILL=no # Normal exit status SuccessExitStatus=143 [Install] WantedBy=multi-user.targetCopy the code

Refresh the configuration

systemctl enable elasticsearch.service
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Commands related to Elasticsearch services

Elasticsearch. service systemctl restart elasticSearch. service systemctl restart elasticsearch.service Elasticsearch. service systemctl disable ElasticSearch. service Systemctl enable elasticSearch. serviceCopy the code

Error exception and resolution

  • Error when using root user:

Switch to a non-root user and run ElasticSearch

[root@xxx bin]# su elasticuser
[elasticuser@xxx bin]$ ./elasticsearch

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  • Insufficient memory error:

# Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x0000000085330000, 2060255232, 0) failed; error='Cannot allocate memory' (errno=12)

The killed service released the memory

./elasticsearch
killed 
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JVM space allocation is changed because elasticsearch7.12.1 has a default JVM space allocation of 4g

Modify jvm.options in config of elasticSearch installation directory

vim config/jvm.options 

-xms1g -xmx1g #Xms512m #Xmx512m #Xms512mCopy the code

Save the configuration file and restart it

./elasticsearch
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  • Startup error:

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

The maximum virtual memory is too small. Add a line at the end of /etc/sysctl.conf

vm.max_map_count=655360
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The /sbin/sysctl -p command takes effect immediately

/sbin/sysctl -p
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Restart ElasticSearch

./elasticsearch
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