Varnish vs Redis Caching differnce in Magento2

[Vineethekm]

Currently we are using redi backend for defult and page cache in magento2.  The env.php can be find below. 

'cache' => [
'frontend' => [
'default' => [
'id_prefix' => 'def_',
'backend' => 'Cm_Cache_Backend_Redis',
'backend_options' => [
'server' => '**********',
'database' => '1',
'port' => '6379',
'password' => ''
]
],
'page_cache' => [
'id_prefix' => 'def_',
'backend' => 'Cm_Cache_Backend_Redis',
'backend_options' => [
'server' => '**********',
'database' => '2',
'port' => '6379',
'compress_data' => '0',
'password' => ''
]
]
]

We introduced varnish from admin side by changing store settings. While checking varnish is hitting with cache but couldn't find any configuration changes on env.php

Should I remove page_cache section from the env.php or still it's redqired?

Any help would be greatly appreciated.

[Sunil Patel · Accepted solution]

Hello @Vineethekm 

if you are using varnish cache then it will not use the page_cache tag from env.php

but if you  are not using varnish then it will use.

but if you are using varnish cache then you need to add

 'http_cache_hosts' => [
        [
            'host' => '52.43.192.118',
            'port' => '80'
        ]
    ],

Hope it will clear your doubts, if works then mark as a solution.

[Vineethekm]

Thank you @Sunil Patel. Much appreciated. 

This is the step to add that conf by CLI.

./magento setup:config:set --http-cache-hosts=127.0.0.1,127.0.0.1:6081 Conf:- 

'http_cache_hosts' => [
[
'host' => '127.0.0.1'
],

[Sunil Patel]

@Vineethekm 

ya you can set backend host for varnish using command that is good  

make sure you need to download vcl file from admin you need to configure it for varnish