Elastic Stack 8 : Elasticsearch インストール2022/12/09

	全文検索エンジン Elasticsearch をインストールします。
[1]	Elasticsearch をインストールして起動します。 Java のインストールは不要です。Elasticsearch に統合されています。

[root@dlp ~]#

cat > /etc/yum.repos.d/elasticsearch.repo <<EOF
[elasticsearch-8.x]
name=Elasticsearch repository for 8.x packages
baseurl=https://artifacts.elastic.co/packages/8.x/yum
gpgcheck=1
gpgkey=https://artifacts.elastic.co/GPG-KEY-elasticsearch
enabled=1
autorefresh=1
type=rpm-md
EOF

[root@dlp ~]#

update-crypto-policies --set DEFAULT:SHA1

[root@dlp ~]#

dnf -y install elasticsearch

.....
.....
--------------------------- Security autoconfiguration information ------------------------------

Authentication and authorization are enabled.
TLS for the transport and HTTP layers is enabled and configured.

The generated password for the elastic built-in superuser is : WsdNReT=WiRbB__*Ejal

If this node should join an existing cluster, you can reconfigure this with
'/usr/share/elasticsearch/bin/elasticsearch-reconfigure-node --enrollment-token <token-here>'
after creating an enrollment token on your existing cluster.

You can complete the following actions at any time:

Reset the password of the elastic built-in superuser with
'/usr/share/elasticsearch/bin/elasticsearch-reset-password -u elastic'.

Generate an enrollment token for Kibana instances with
 '/usr/share/elasticsearch/bin/elasticsearch-create-enrollment-token -s kibana'.

Generate an enrollment token for Elasticsearch nodes with
'/usr/share/elasticsearch/bin/elasticsearch-create-enrollment-token -s node'.

-------------------------------------------------------------------------------------------------

[root@dlp ~]#

systemctl enable --now elasticsearch

# 動作確認
# パスワードはインストール中に表示されたパスワードで応答

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt https://127.0.0.1:9200

Enter host password for user 'elastic':
{
  "name" : "dlp.srv.world",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "ilb6UzwQQdiBj752QE0YmQ",
  "version" : {
    "number" : "8.5.3",
    "build_flavor" : "default",
    "build_type" : "rpm",
    "build_hash" : "4ed5ee9afac63de92ec98f404ccbed7d3ba9584e",
    "build_date" : "2022-12-05T18:22:22.226119656Z",
    "build_snapshot" : false,
    "lucene_version" : "9.4.2",
    "minimum_wire_compatibility_version" : "7.17.0",
    "minimum_index_compatibility_version" : "7.0.0"
  },
  "tagline" : "You Know, for Search"
}

[2]	Elasticsearch を他ホストからも利用する場合は、クラスターの設定を参照ください。クラスター構成ではないシングルホストの場合でも、他ホストからのリクエストを受け付ける場合は、同様の設定が必要です。
[3]	日本語が扱えるようにプラグインをインストールします。

# analysis-kuromoji インストール

[root@dlp ~]#

/usr/share/elasticsearch/bin/elasticsearch-plugin install analysis-kuromoji

-> Installing analysis-kuromoji
-> Downloading analysis-kuromoji from elastic
[=================================================] 100%  
-> Installed analysis-kuromoji
-> Please restart Elasticsearch to activate any plugins installed

# インストール済みプラグイン表示

[root@dlp ~]#

/usr/share/elasticsearch/bin/elasticsearch-plugin list

analysis-kuromoji

[4]	基本的な使い方です。まず最初に Index を作成します。RDB のデータベースに相当する概念です。

# Index 一覧を表示 (pretty は JSON 形式の表示を見易くするオプション)

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt https://127.0.0.1:9200/_aliases?pretty

Enter host password for user 'elastic':
{
  ".security-7" : {
    "aliases" : {
      ".security" : {
        "is_hidden" : true
      }
    }
  }
}

# Index 作成

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt -X PUT "https://127.0.0.1:9200/test_index"

Enter host password for user 'elastic':
{"acknowledged":true,"shards_acknowledged":true,"index":"test_index"}

# 確認

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt https://127.0.0.1:9200/_aliases?pretty

Enter host password for user 'elastic':
{
  ".security-7" : {
    "aliases" : {
      ".security" : {
        "is_hidden" : true
      }
    }
  },
  "test_index" : {
    "aliases" : { }
  }
}

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt https://127.0.0.1:9200/test_index/_settings?pretty

Enter host password for user 'elastic':
{
  "test_index" : {
    "settings" : {
      "index" : {
        "routing" : {
          "allocation" : {
            "include" : {
              "_tier_preference" : "data_content"
            }
          }
        },
        "number_of_shards" : "1",
        "provided_name" : "test_index",
        "creation_date" : "1624321329152",
        "number_of_replicas" : "1",
        "uuid" : "Vh0HutpLRciaMWX3pFo7Zg",
        "version" : {
          "created" : "7130299"
        }
      }
    }
  }
}

[5]	Mapping とテストデータの投入を実行します。 Mapping は Index の構造を定義するものです。データを投入すると自動で Mapping 定義されますが、手動で定義することももちろん可能です。

# データ投入

[root@dlp ~]# curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt \
-H "Content-Type: application/json" \
-X PUT "https://127.0.0.1:9200/test_index/_doc/001" -d '{
    "subject" : "Test Post No.1",
    "description" : "This is the initial post",
    "content" : "This is the test message for using Elasticsearch."
}'
Enter host password for user 'elastic':
{"_index":"test_index","_id":"001","_version":1,"result":"created","_shards":{"total":2,"successful":1,"failed":0},"_seq_no":0,"_primary_term":1}

# Mapping 確認

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt "https://127.0.0.1:9200/test_index/_mapping/?pretty"

Enter host password for user 'elastic':
{
  "test_index" : {
    "mappings" : {
      "properties" : {
        "content" : {
          "type" : "text",
          "fields" : {
            "keyword" : {
              "type" : "keyword",
              "ignore_above" : 256
            }
          }
        },
        "description" : {
          "type" : "text",
          "fields" : {
            "keyword" : {
              "type" : "keyword",
              "ignore_above" : 256
            }
          }
        },
        "subject" : {
          "type" : "text",
          "fields" : {
            "keyword" : {
              "type" : "keyword",
              "ignore_above" : 256
            }
          }
        }
      }
    }
  }
}

# データ確認

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt "https://127.0.0.1:9200/test_index/_doc/001?pretty"

Enter host password for user 'elastic':
{
  "_index" : "test_index",
  "_id" : "001",
  "_version" : 1,
  "_seq_no" : 0,
  "_primary_term" : 1,
  "found" : true,
  "_source" : {
    "subject" : "Test Post No.1",
    "description" : "This is the initial post",
    "content" : "This is the test message for using Elasticsearch."
  }
}

# データ検索
# 例の検索条件は [description] に [initial] 含む

[root@dlp ~]#

curl -u elastic --cacert /etc/elasticsearch/certs/http_ca.crt "https://127.0.0.1:9200/test_index/_search?q=description:initial&pretty=true"

Enter host password for user 'elastic':
{
  "took" : 12,
  "timed_out" : false,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : {
      "value" : 1,
      "relation" : "eq"
    },
    "max_score" : 0.2876821,
    "hits" : [
      {
        "_index" : "test_index",
        "_id" : "001",
        "_score" : 0.2876821,
        "_source" : {
          "subject" : "Test Post No.1",
          "description" : "This is the initial post",
          "content" : "This is the test message for using Elasticsearch."
        }
      }
    ]
  }
}