Durga Shankar Gupta

Redis is an open source (BSD licensed), in-memory data structure store, used as a database, cache and message broker. It supports data structures such as strings, hashes, lists, sets, sorted sets with range queries, bitmaps, hyperloglogs and geospatial indexes with radius queries. Redis has built-in replication, Lua scripting, LRU eviction, transactions and different levels of on-disk persistence, and provides high availability via Redis Sentinel and automatic partitioning with Redis Cluster.

Configure Redis Cache for Magento 2

To enable caching in redis, extend your <root dir>/app/etc/env.php with the following snippet. Add this in between the cache keys. (Without the cache key in the snippet)

 

'cache' => array(
    'frontend' => array(
        'default' => array(
            'backend'         => 'Cm_Cache_Backend_Redis',
            'backend_options' => array(
                'server' => '127.0.0.1',
                'port'   => '6379',
            ),
        ),
    ),
),

Now flush your cache:</>

rm -rf <root dir>/var/cache/*
redis-cli flushall

Configure Redis Full Page Caching for Magento 2

To enable page caching redis, extend your <root dir>/magento2/app/etc/env.php with the following snippet.
You should paste this in between the cache keys, so leave the cache tag in this snippet out of it.

'cache' => array (
        'frontend' => array (
            'default' => array (
                'backend'         => 'Cm_Cache_Backend_Redis',
                'backend_options' => array (
                    'server' => '127.0.0.1',
                    'port'   => '6379',
                ),
            ),
            // Start of snippet
            'page_cache' => array (
                'backend'         => 'Cm_Cache_Backend_Redis',
                'backend_options' => array (
                    'server'        => '127.0.0.1',
                    'port'          => '6379',
                    'database'      => '1',
                    'compress_data' => '0',
                ),
            ),
            // End of snippet
        ),
),

Now flush your cache:

rm -rf <root dir>/var/cache/*
redis-cli flushall

Flush your caches
To flush your magento cache, clear the redis database corresponding to your configured redis database:

redis-cli -n $db flushdb 
## Flush using n98-magerun2 
n98-magerun2 cache:flush 

## Flush using magento cli

cd <root dir> && php bin/magento cache:flush

To flush all sessions, caches etc (flush the full redis instance), use the following command:

redis-cli flushall

Troubleshooting

A more extended how-to about configuring redis caches can be found on the magento help pages