Right now the SunBlog(v2.3.18) have implemented the export/import feature which make it IPortable.
Import
Imporing data into your blog is many times, necessary and useful. If you are moving from another host, or just to start your blog anew, then import data into your blog may be the answer. Right now SunBlog supports the importing data feature. In many cases, posts, comments, categories, tags, and users, can be imported. In future version, it will support import content from a number external sources, i.e the DNN core blog or other blog engines.
Export
Exporting your blog data (posts, comments, custom fields, categories, and tags) is sometimes necessary and useful. If you are moving to a new host, export content from you local machine to deploy on your production server or just want a backup of your blog, then Exporting your blog is the answer. SunBlog Export will create an XML file for you to save to your website. The format file will contain your posts, comments, custom fields, categories, and tags. Once the Export file is created, that file can be used for import by “Import Panel”.