I want to run elasticsearch with my tomcat server and index the data pulling from database and put it in elasticsearch index. Any pointers will help.
Elasticsearch has a Java API that you can use to do what you want to: https://www.elastic.co/guide/en/elasticsearch/client/java-api/current/index.html
If you are new to ES Definitive Guide is a very very good document: https://www.elastic.co/guide/en/elasticsearch/guide/current/index.html
By the way Elasticsearch is a full-text search engine. If you are looking an in memory data solution may be you should consider something like Apache Ignite: http://ignite.apache.org/
Related
I'm using JanusGraph with ElasticSearch and Cassandra.
My question is how JanusGraph stores the data when I create a new entity in case that I'm using two databases (JanusGraph and ElasticSearch)
I could understand that ElasticSearch is used as index backend and Cassandra is the storage, but:
What JanusGraph does when I persist a new data ? It'll duplicate the same data into Cassandra and also on ElasticSearch (because it's also a database)?
If the answer for the first item is yes, so, when we perform a query that will traversal the graph, the JanusGraph will understand and perform the query on Cassandra and when this is a full text search then JanusGraph switch the query to ElasticSearch ?
If the answer for the first item is no, so, all the data will be stored on Cassandra and in some way JanusGraph will just use the index from ElasticSearch to do a search on Cassandra database ?
ElasticSearch indexes the data stored in Cassandra.
When you do graph traversals, it uses the search index to retrieve the data from Cassandra. Cheers!
Just going to implement elastic search log related task.
Have some questions about elastic:
What is elastic? does it mean flexible stuff?
What is elastic search? (https://www.elastic.co/products/elasticsearch)
what is elastic cache?
what is the relationship between elastic search and elastic cache?
Thanks
I'm not sure what relates ES with EC, but simply Elastic Search is where you index all the data you need, let it be log files or the data from a database. You could store them as docs within an index and then query in order retrieve data from the index.
This is what I got from my neighborhood friend Google:
Elasticsearch is a search engine based on Lucene. It provides a
distributed, multitenant-capable full-text search engine with an HTTP
web interface and schema-free JSON documents.
Disclaimer: I am very new to ELK Stack, so this question can be very basic.
I am setting up ELK stack now. I have below basic questions about ElasticSearch.
What is the storage model elastic search is following?
For example Oracle is using relational model ,Alfresco is using "document model" and Apache Jackrabbit is using "hierarchial model"
2.Log data stored in elastic search is persistent/permanent ? Or ElasticSearch deletes log data after certain period?
3.How we will manage/backup this data?
4.Log/data files in Elastic Search is human-readable?
Any help/route to documentation will be appreciated.
the storage model is a Document model. Everything is a document. The documents are of a particular type and they are stored in an index.
Data send to ES is stored on disk. It can be then read, searched or deleted through a REST API.
The Data is managed through the rest API. Usually for log centralisation, the logs are stored in date-based index (one index for today, one for yesterday and so on), so to delete the logs from one day, you delete the relevant index. Curator can help in this case. ES offers a backup and restore module.
To access the data in ES, you'll have to use the REST API or use the Kibana client.
Documentation:
https://www.elastic.co/guide/en/elasticsearch/guide/current/index.html
https://www.elastic.co/guide/en/elasticsearch/reference/current/index.html
How are events indexed and stored by Elasticsearch when using ELK (Elastichsearch, Logstash, Kibana)
How does Elasticsearch work in ELK
Looks like you got downvoted for not just reading up at elastic.co, but...
logstash picks up unstructured data from log files and other sources, transforms it into structured data, and inserts it into elasticsearch.
elasticsearch is the document repository. While it's not useful for log information, it's a text engine at heart and can analyze the data (tokenization, stop words, stemming, etc).
kibana reads from elasticsearch and allows you to explore the data and make dashboards.
That's the 30,000-ft overview.
Elasticsearch have the function of database on ELK Stack.
You can read more information about Elasticsearch and ELK Stack here: https://www.elastic.co/guide/en/elasticsearch/guide/current/index.html.
first of all you will have logs file that you used to write system logs on it
for example when you add new record to database you will write the record in any form you need to log file like
date,"name":"system","serial":"1234" .....
after that you will add your configuration in logstash to parse the data from the logs
and it will be like
name : system
.....
and the data will saved in elastic search
kibana is used to preview the elastic search data
and you can use send a request to elasticsearch with the required query and get your data from it
I'm new to ElasticSearch and am trying to figure out what is the most optimal way to index 1 Terabyte of data in Cassandra.
Two options that I understand right now are:
Move data periodically to ElasticSearch using the Cassandra-River plugin and then run index on the data.
Advantage: Search queries create no impact on Cassandra load
Disadvantage: Have to sync the data periodically
Without moving the data run ElasticSearch on Cassandra to index the data (not sure how will this be done).
Advantage: Data always in sync
Disadvantage: Impacts Cassandra performance ?
Any thoughts would be appreciated.
Prehaps in the context of ElasticSearch 1.4 and above.. just using ElasticSearch as a datastore and search engine might be simpler and elegant option.
Add more nodes to scale.