The odd issue where WP-CLI over a VPN timed out during large DB exports and the chunked dump approach that completed backups reliably

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It was a peaceful Tuesday. Birds were chirping, coffee was brewing, and our team settled in for what was supposed to be a routine WordPress database export. But instead of success, we found ourselves in an oddly specific, super frustrating situation: WP-CLI timed out during large DB exports… only over VPN. Yes, it was as weird as it sounds.

TL;DR

When exporting large WordPress databases using WP-CLI while connected via a VPN, the process would randomly timeout or hang. After many trials and errors, we discovered that breaking the export into smaller chunks reliably avoided the timeout issue. This “chunked dump” approach worked beautifully and sped up the process. Now, backups are smooth even over questionable networks.

The Setup: A Simple Backup

Our mission was straightforward — back up a WordPress site’s database using WP-CLI. We do this regularly to migrate sites or create staging environments. The command looks simple enough:

wp db export backup.sql

Normally this runs fine. But here’s where things went sideways — when we were connected to the company VPN.

Suddenly… Timeout City

The process would start just fine. WP-CLI kicked off the export, and the spinning cursor gave us hope. But after a while, boom! It would hang. Freeze. Or just… vanish with a broken pipe error. Every. Single. Time.

We tried re-running it. Different servers. Different sites. The problem only happened under one condition: exporting large databases over VPN using WP-CLI.

The first hunch was a flaky internet connection. But nope. We did speed tests. We pinged servers. Everything was stable. Then we suspected WP-CLI itself. So we updated it. Still failed.

The database wasn’t enormous either — around 1.8 GB. It wasn’t a monster. But it was big enough, we found, to cause trouble over VPN.

It’s Not You, It’s VPN

We had a theory: maybe large data streams were triggering some kind of timeout or buffer overflow. VPNs are great for security, but sometimes the tunnel isn’t as big as we want it to be.

It seemed like the constant stream of data from WP-CLI just overwhelmed the VPN or got throttled. Either way, it stalled out mid-process. Sometimes after 30%, sometimes 80%. No pattern, just pure chaos.

The Workaround: A Chunky Solution

So how do you back up a big database without it crashing mid-export? Answer: chunk it.

We modified our approach. Instead of dumping the whole thing at once, we created smaller, digestible pieces. Like cutting a giant pizza into slices instead of trying to swallow it whole.

Here’s how we did it:

  1. Export only certain tables at a time.
  2. Start with the basic structure.
  3. Then group tables by size or importance.

Basically, we ran individual wp db export commands with table names:

wp db export backup-structure.sql --add-drop-table --no-data
wp db export backup-content.sql --tables wp_posts wp_postmeta
wp db export backup-analytics.sql --tables wp_statistics wp_logs

And so on. Each command created a smaller file. These were zippy, didn’t trigger any network weirdness, and completed without issues.

A Little Script Helped A Lot

We automated things with a simple Bash script. It grouped our tables, then ran exports one after the other with brief pauses in between. That gave the VPN a breather and kept the process stable.

Here’s a taste of the script logic:


#!/bin/bash
wp db export structure.sql --add-drop-table --no-data

# Export content-related tables
wp db export content.sql --tables wp_posts wp_postmeta

# Export analytics separately
wp db export analytics.sql --tables wp_statistics wp_logs

# Pause to ensure network is stable
sleep 5

It wasn’t rocket science. But it worked — like magic.

Why Chunking Works

We’re not VPN engineers, but here’s the theory in layman’s terms.

  • VPNs encrypt and reroute data through tunnels. But long streams of nonstop data can get jammed.
  • WP-CLI’s export dumps everything in one shot. That’s a lot of data moving very fast.
  • Breaking it into smaller pieces gives your VPN time to breathe and handle the transfers more efficiently.

Also, smaller files are easier to retry if something goes wrong. No need to start over from scratch.

Bonus Tip: Compress as You Go

One more trick: use gzip while exporting. Like this:

wp db export - | gzip > backup.sql.gz

This reduces file size and speeds up transfers. Not all systems handle live compression well, so test it on your setup. But when it works, it’s a lifesaver.

Putting It All Together

Here’s what our updated export process looks like now:

  1. Start VPN connection.
  2. Run chunked WP-CLI export via script.
  3. Compress files as needed.
  4. Upload or move backups to remote storage.

Reliability went up. Stress went down. Success became the norm!

Moral of the Story: Don’t Fight the VPN

Sometimes it’s not about brute force. Especially with stubborn tech issues. It’s about working smarter.

That little “chunking” idea made all the difference. It’s easy, it’s clean, and it brought sanity back to our backups.

Looking Forward

We now include this approach by default in our backup scripts. Anytime we suspect network inconsistencies, especially over VPNs, we don’t risk full dumps anymore.

And if you’re reading this while sipping cold coffee, watching your WP export fail for the fifth time — give chunking a try. It might just save your day too!

Happy Dumping 😄

Database dumping, we mean! Stay secure, stay backed up — and occasionally, slice your backups into pizza-sized pieces. Because sometimes, that’s exactly what the doctor (or sysadmin) ordered!