如何解决WordPress更新文章时的连接丢失及404错误

Hey Anna, let's dig into this issue—since creating posts works fine but updating throws errors, we can rule out some broad server or setup issues right away. Let's break down possible causes and steps to test:

First: Is the 1-Core CPU the Problem? #

20k weekly visits is manageable on a 1-core CPU with proper optimization, especially since creating posts works (that's a similar write operation). Before upgrading, check your server's CPU load while you're trying to update a post:

• Use tools like top or htop via SSH to watch real-time CPU usage. If it's spiking to 90-100% and staying there during updates, resource constraints might be a factor. But if load stays low, this is almost certainly not a CPU issue.

Focus on the Update-Specific Behavior #

Since creating posts works, the problem is tied to the update workflow—here are key areas to check:

1. Check Server & Application Error Logs #

This is the most critical step. Look for logs related to your web server (Apache/Nginx) and CMS:

• For Apache: Check /var/log/apache2/error.log or /var/log/httpd/error.log
• For Nginx: Check /var/log/nginx/error.log
• For WordPress: Enable WP_DEBUG in wp-config.php (set define('WP_DEBUG', true);) to see backend errors during updates.

Look for entries that match the timing of your update attempts—you might see:

• 404 errors indicating the update endpoint (like wp-json/wp/v2/posts/{post-id}) is being blocked or redirected incorrectly
• Database errors (e.g., lock issues, missing permissions for updating post records)
• Timeout errors (server killing the update request before it completes)

2. Test Update Behavior Across Different Posts #

Is the error happening with all posts, or just a specific one?

• If it's only one post, check for unusual content: extremely long text, special characters, broken shortcodes, or custom fields that might be causing a database write failure.
• If it's all posts, the issue is likely a global configuration or routing problem.

3. Verify Permalink & Rewrite Rules #

You mentioned updating permalinks already, but double-check:

• If you're using a CMS like WordPress, make sure the rewrite rules are correctly applied (flush them again via Settings > Permalinks, or via CLI with wp rewrite flush if you have WP-CLI installed).
• Check your .htaccess file (Apache) or Nginx config to ensure there aren't rules that block or redirect post update endpoints.

4. Check Server Timeout Settings #

Update requests might take slightly longer than create requests (e.g., if they trigger cache purges or additional post-processing). If your server has tight timeout limits, it could kill the connection mid-process:

• For Apache: Adjust the Timeout directive in your config (default is usually 300s, but try increasing it temporarily to test).
• For Nginx: Check fastcgi_read_timeout (if using PHP-FPM) and proxy_read_timeout—increase these values if they're set too low.

5. Rule Out Cache Conflicts #

If you're using a caching plugin or server-level cache:

• Temporarily disable all caching tools (page cache, object cache, CDN) and test updating a post. Sometimes cache purging during updates can cause race conditions or invalid redirects.
• If disabling cache fixes the issue, check the cache plugin's settings for post update triggers—make sure it's not blocking the update endpoint or causing premature purges.

6. Database Permissions & Locking #

Creating posts works, so your database user has write permissions—but updating requires modifying existing records. Check:

• Are there database table locks happening during updates? Use tools like mysqladmin status to see if tables are locked when you try to update.
• Verify your database user has UPDATE permissions on the posts table (and related meta tables).

Final Thought on CPU Upgrades #

Start with the above troubleshooting steps first—hardware upgrades should be a last resort. If all else fails and you confirm CPU load is maxing out during updates, adding an extra core could help, but it's unlikely to fix the root cause here given the create/update discrepancy.

内容的提问来源于stack exchange，提问作者Anna