WordPress Import: Common Issues with Site Migration, Backup and Restore

Among WordPress’s built-in tool options, several site backup and migration services are provided under “Import”, which can quickly import posts and media from common content platforms such as Blogger, LiveJournal, Movable Type, Typepad, RSS, and Tumblr (a dedicated plugin must be installed separately).

And of course, WordPress’s own system has a corresponding official backup plugin, “WordPress Importer”, which lets site owners migrate and back up WP sites through the plugin.

This official WordPress Importer plugin provides backup and restore functions that can fully back up and restore standard content such as posts, pages, comments, custom fields, categories, and tags on a WP site, which is already sufficient for ordinary blogger users.

The WordPress content importer “WordPress Importer” must be installed by ourselves, and it corresponds to the WP system’s built-in “export” tool. Both the importer and the exporter are located in the “Tools” menu in the backend sidebar. We need to export a file (XML) first before we can run the importer on the new site.

All-in-One WP Migration vs. WordPress Importer

Earlier, in the article “WordPress Site Migration and Backup Plugin ‘All-in-One WP Migration’ Alternatives”, I introduced several ways to use WP site migration and backup plugins. The most recommended one is “All-in-One WP Migration”, which is also used by many WordPress hosting providers (such as Bluehost). It can fully back up the entire site content and database, and restoration is almost indiscriminate.

Even so, there are times when you still want to use the most natural Importer, for example when you feel the site database is full of junk data slowing down site performance. Then we can restore using only the plain post content.

504 Gateway Time-Out

Users who have used WordPress Importer may have some complaints, because problems often occur during the import process, causing the site migration and restoration process to be riddled with errors.

WordPress Importer import timeout

The image above shows one of the most common situations I encounter: a “504 Gateway Time-Out” during the import process.

Generally speaking, if a website shows an HTTP 504 status code (Gateway Timeout), it means the origin server did not respond within the request timeout. This can be addressed by modifying the execution time value in the server’s PHP.INI configuration file to allow more processing time.

However, different sites have different corresponding times. In practice, there is a simple way to solve this problem: when the page in the image above completely stops working, press the “F5” key, or click the “Reload this page” button in the browser toolbar, to make that HTTP 504 page execute again directly.

Afterwards, when the page stops working again, repeat the above steps until the import job fully succeeds and automatically returns to the normal site page. Only then is the import job truly complete.

Media Library Backup Issues

Besides posts, the most troublesome part of a website is the various photos, documents, videos, audio, and other media files referenced in posts. Over the years, it is common for the library to hold hundreds of MB or even several GB. A complete site backup cannot lack these media files.

In fact, WordPress’s built-in export function cannot directly export media files, but they can be imported.

Doesn’t that sound amazing?

The actual working principle is that during the import process, the importer automatically fetches media files from the original site.

But then a new problem arises. If you are copying a site to a different location (for example, copying a site on domain A to a site on domain B), that is fine, but if you are simply changing servers, you naturally cannot obtain the source files from the old server.

Therefore, a safer approach is to not check the “Import media files” option during the import process.

We can first import posts, users, categories, tags, and other internal information to build the rough skeleton of the site and avoid a major impact on user experience. Then, move the media library folder “uploads” from the original server to the same location on the new server (hint commands: tar, wget), and afterwards run the importer again, this time checking the “Import media files” option.

Media Files Cannot Be Added