Filling holes in the installation of ElasticSearch on CentOS7

Download elasticsearch 5.3.0wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-5.3.0.tar.gzmv elasticsearch-5.3.0.tar.gz / optcd / opttar-xzvf elasticsearch-5.3.0.tar.gzcd elasticsearch-5.3.0/ to start EScd / bin./elasticsearch

According to the reason, it should be OK, but then all kinds of pits appear one by one and elaborate separately.

Error 1:error='Cannot allocate memory' (errno=12)

Solutions:

Since the default jvm space allocated by elasticsearch6.0 is 2g, it needs to be reduced a bit.

Vim config/jvm.options-Xms2g →-Xms512m-Xmx2g →-Xmx512m

Error 2: can not run elasticsearch as root

Solutions:

In a Linux environment, elasticsearch is not allowed to run with root privileges! So you need to create a non-root user to start es with a non-root user

Groupadd elk # create user group elkuseradd elk-g elk-p 111111 # create new user elk,-g elk set its user group to elk,-p 111set its password 6 1chown-R elk:elk / opt # change / opt folder and internal files belong to elk:elksu elk # switch to non-root user elk

Error 3: (1) max file descriptors [4096] for elasticsearch process is too low, increase to at least [65536]

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

This error occurs when you modify the network.host in config/elasticsearch.yml to network.host: 0.0.0.0 so that any IP on the public network can access it.

Solutions:

Switch to the root user, and

Vim / etc/security/limits.conf* soft nofile 300000 * hard nofile 300000 * soft nproc 102400 * soft memlock unlimited* hard memlock unlimited

Error 4:max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]

Solutions:

First you need to switch to the root user

You can then execute the following command to set the vm.max_map_count, but it will return to the original value after reboot.

Sysctl-w vm.max_map_count=262144

Persistence is done by modifying the vm.max_map_count parameter in the / etc/sysctl.conf file:

Echo "vm.max_map_count=262144" > / etc/sysctl.confsysctl-p

Finally, the access to the public network is successful:

Install the visualization plug-in elasticsearch-headgit clone git://github.com/mobz/elasticsearch-head.gitcd elasticsearch-headnpm install # here I am trying to use cnpm install has a problem, using npm can npm run start

Then visit http:// your installation machine IP:9100 on the public network.

Finally, a simple test is actually done.

If you create a new Index, you can send a PUT request directly to the Elastic server. The following example is a new Index called weather.

However, refreshing the elasticsearch-head visual interface shows that the index has been inserted successfully

Postscript

More elastic search practices about the author are here