$from_redis = redis_init($from);
$to_redis = redis_init($to);

$keys = $from_redis->keys('*');
$count = 0;
$total = count($keys);
foreach($keys as $key){
if(++$count % 100 == 1){
echo "$count/$total\n";
}
$type = $from_redis->type($key);
switch($type){
case Redis::REDIS_STRING:
$val = $from_redis->get($key);
$to_redis->set($key,$val);
break;
case Redis::REDIS_LIST:
$list = $from_redis->lRange($key,-1);
foreach($list as $val){
$to_redis->rPush($key,$val);
}
break;
case Redis::REDIS_HASH:
$hash = $from_redis->hGetAll($key);
$to_redis->hMSet($key,$hash);
break;
case Redis::REDIS_ZSET:
$zset = $from_redis->zRange($key,-1,true);
foreach($zset as $val=>$score){
$to_redis->zAdd($key,$score,$val);
}
break;
}
}

function redis_init($conf){
$redis = new Redis();
preg_match('/^([^:]+)(:[0-9]+)?\\/(.+)?/',$conf,$ms);
$host = $ms[1];
$port = trim($ms[2],':');
$db = $ms[3];
$redis->connect($host,$port);
$redis->select($db);
return $redis;
}