Redis is in-memory data structure store, used as database, cache and message broker. It stores data on disk and also in memory. We can call it as permanent + memory storage. It supports data types like regular databases … string hash list set sorted sets It supports various queries and provides high availability via Redis Sentineland Read More
Install logstash-forwarder yum install https://download.elastic.co/logstash-forwarder/binaries/logstash-forwarder-0.4.0-1.x86_64.rpm Add config file in location – /etc/logstash-forwarder.conf { "network": { "servers": [ "localhost:5000" ], "timeout": 15, "ssl ca": "/etc/pki/tls/certs/logstash-forwarder.crt" }, "files": [ { "paths": [ "access_log" ], "fields": { "type": "access" } } ] } You can access above field “type” in logstash and use it in filter or output Read More
We can redirect every request received in squid to custom php script and we can process those request before returning back to the client. This can be done using url_rewrite_program in squid config. Just add following line at the end of url squid.conf file. url_rewrite_program /etc/process.php And here is process.php #!/usr/bin/php <?php while ($input = fgets(STDIN)) Read More
Latest elasticsearch has new future of Alerting for elasticsearch using Watcher. This feature is very important and helpful to trigger alert on matching search query. You need to install plugin bin/plugin -i elasticsearch/license/latest bin/plugin -i elasticsearch/watcher/latest #Restart elasticsearch #Verify installation using curl -XGET 'http://localhost:9200/_watcher/stats?pretty' After installation we have to create watcher index. This will check for Read More
Using OpenCV and python script we could able detect face from image. Here is sample code for it, but some times there is false detection due to image not clear. Here are some factors can affects face detection … Face in the image not clear. High definition colored image. Very big sized. Image having design Read More
We can change mysql root password by using following steps. Here is simple command for it. service mysqld stop service mysqld startsos mysql -u root UPDATE mysql.user SET Password=PASSWORD(‘NEWPWD’) WHERE User=’root'; FLUSH PRIVILEGES; service mysqld restart
If we have documents of city information, in elasticsearch we can implement auto-complete search using nGram filter. Add index mapping as following … curl -X PUT "http://localhost:9200/cities" -d '{ "mappings" : { "city" : { "properties" : { "name" : { "type" : "string", "search_analyzer" : "apps_search", "index_analyzer" : "apps_index" }, "state": {"type" : "string"}, Read More
We can setup script for connect vpn from command line on centos linux. Following are couple of steps but before that, you need to install pptp and pptpsetup on linux. Run following command with your credentials … pptpsetup –create <vpn connection name> –server <vpn host> –username <login username> –password <login password> –encrypt You need to Read More
Elasticsearch has capability to create custom plugins by inheriting its core classes and functionality. We can implement java code as per our requirement easily plug with elasticsearch. Following are the steps to do that … Create folder structure – Following is sample plugin file structure, its recommended by elasticsearch and its standard way of doing things. Read More
Even if elasticsearch is distributed, highly available but it has some limitation over multiple data center. So creating DR of elasticsearch is some what tricky. So in this case backup of whole elasticsearch cluster is very important. With latest version of elasticsearch, snapshot and restore api included. http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/modules-snapshots.html Here are following steps to backup your Read More
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