http://www.opencart.com/index.php?route=extension/extension/info&extension_id=19572
下载 OpenCart Migration & Upgrade Tool version 2.0.5
将 2.1.0.1/upload/ 覆盖到 1.5.6.4 目录
http://testopencart/converter/readme.php
再将 OpenCart-Migration-Upgrade-Tool-2.0.5/upload/ 覆盖到 1.5.6.4 目录
http://testopencart/converter/index.php
Administrative permission - Save Initial - Initial Upgrade - To Upgrade The Database
勾选Upgrade database to version 2.1.0.1
Start with update
Update config files
Continue
Finish
如果出现：
Notice: Use of undefined constant DIR_MODIFICATION - assumed 'DIR_MODIFICATION' in xxx
vi config.php
define('DIR_MODIFICATION', 'xxxxxx/system/modification/');
Notice: Use of undefined constant DB_PORT - assumed 'DB_PORT' in xxx
vi config.php
define('DB_PORT', '3306');
执行一遍如下操作
http://testopencart/install/index.php
将 2.3.0.2/upload/ 覆盖到之前的目录
http://testopencart/install/index.php
Upgrade
chmod -R 777 system/storage/cache/
如果出现：
Warning: is_file(): open_basedir restriction in effect. File(xxx/../../vendor/autoload.php) is not within the allowed path(s)
cd web目录
mkdir ../upload/
mv ./* ../upload/
mv ../upload/ ./
将 2.3.0.2/vendor/ 拷贝到当前目录
修改 nginx 配置以及 opencart 中的各目录配置
Warning: fopen(xxx/upload/system/storage/logs/openbay.log): failed to open stream: Permission denied
chmod -R 777 upload/system/storage/logs/
rm -rf install/
rm -rf converter/
如果打开 Dashboard 很慢，则关闭关闭自动更新汇率（Dashboard>System>Setting>Your Store>edit>local>Auto Update Currency 选择No）
下载语言包
http://www.opencart.com/index.php?route=extension/extension/info&extension_id=15172&filter_search=chinese&filter_license=0
拷贝到对应目录
添加语言包：
System - Localisation Languages - 右上角 Add
简体中文，zh-cn，zh-CN,zh-CN.UTF-8,zh-cn
Store设置 - Language - 简体中文
如果产品页面载入慢
catalog\view\theme\default\template\product\product.tpl
删除 tweet 和 facebook 相关内容