diff --git a/cache/stores/redis/addinstanceform.php b/cache/stores/redis/addinstanceform.php
index cdd9ed653a3..e480918bcc4 100644
--- a/cache/stores/redis/addinstanceform.php
+++ b/cache/stores/redis/addinstanceform.php
@@ -43,6 +43,7 @@ class cachestore_redis_addinstance_form extends cachestore_addinstance_form {
         $form->setType('server', PARAM_TEXT);
         $form->addHelpButton('server', 'server', 'cachestore_redis');
         $form->addRule('server', get_string('required'), 'required');
+        $form->addElement('static', 'server_desc', '',  get_string('server_desc', 'cachestore_redis'));
 
         $form->addElement('advcheckbox', 'encryption', get_string('encrypt_connection', 'cachestore_redis'));
         $form->setType('encryption', PARAM_BOOL);
diff --git a/cache/stores/redis/lang/en/cachestore_redis.php b/cache/stores/redis/lang/en/cachestore_redis.php
index 7b6cddb30c9..5d4fa37ef1e 100644
--- a/cache/stores/redis/lang/en/cachestore_redis.php
+++ b/cache/stores/redis/lang/en/cachestore_redis.php
@@ -42,12 +42,13 @@ $string['privacy:metadata:redis:data'] = 'The various data stored in the cache';
 $string['serializer_igbinary'] = 'The igbinary serializer.';
 $string['serializer_php'] = 'The default PHP serializer.';
 $string['server'] = 'Server';
-$string['server_help'] = 'This sets the hostname or IP address of the Redis server to use.';
+$string['server_desc'] = 'For Unix socket usage, use the format <strong>/var/redis.sock</strong> or <strong>unix:///var/redis.sock</strong>';
+$string['server_help'] = 'This sets the hostname, IP address or Unix socket path of the Redis server to use.';
 $string['password'] = 'Password';
 $string['password_help'] = 'This sets the password of the Redis server.';
 $string['task_ttl'] = 'Free up memory used by expired entries in Redis caches';
 $string['test_server'] = 'Test server';
-$string['test_server_desc'] = 'Redis server to use for testing.';
+$string['test_server_desc'] = 'Redis server to use for testing.<br>For Unix socket usage, use the format <strong>/var/redis.sock</strong> or <strong>unix:///var/redis.sock</strong>';
 $string['test_password'] = 'Test server password';
 $string['test_password_desc'] = 'Redis test server password.';
 $string['test_serializer'] = 'Serializer';
diff --git a/cache/stores/redis/lib.php b/cache/stores/redis/lib.php
index 3c72c7d7e0e..3b3229302bb 100644
--- a/cache/stores/redis/lib.php
+++ b/cache/stores/redis/lib.php
@@ -217,7 +217,8 @@ class cachestore_redis extends cache_store implements cache_is_key_aware, cache_
         // Check if it isn't a Unix socket to set default port.
         $port = null;
         $opts = [];
-        if ($server[0] === '/') {
+        // Unix sockets can start with / or with unix://.
+        if ($server[0] === '/' || strpos($server, 'unix://') === 0) {
             $port = 0;
         } else {
             $port = 6379; // No Unix socket so set default port.