Preventionlabs – Crash Alerts and Site Check
| 开发者 | preventionlabs |
|---|---|
| 更新时间 | 2026年11月1日 12:19 |
| PHP版本: | 7.4 及以上 |
| WordPress版本: | 7.1 |
| 版权: | GPLv2 or later |
| 版权网址: | 版权信息 |
详情介绍:
- Which plugin or theme broke the site, by name (for out-of-memory and time-limit crashes: which one was running).
- What went wrong. For example: it ran out of memory, a file has broken code, or it needs code that isn't on your site.
- Whether that plugin was updated or turned on shortly before the crash, with the version and how long before.
- How to fix it, including what to do if you can't log in.
Acme Shop crashed your site. The plugin Acme Shop tried to use a piece of code (acme_missing_helper) that isn't on your site. This usually means it needs another plugin that is turned off or missing, or it doesn't match your WordPress or PHP version. It was updated to version 2.0.0, 1 minute before the crash, so the update is the most likely cause. How to fix it: Turn off Acme Shop. In your dashboard, go to Plugins and click Deactivate under it. If you can't log in, open your host's file manager and rename the folder wp-content/plugins/acme-shop to acme-shop-off. If Acme Shop caused the crash, that brings your site back.How it works:
- It uses WordPress's own crash handler (the wp-content/fatal-error-handler.php drop-in), which loads before any plugin. So it also catches crashes in plugins that load before this one. If another plugin already uses that file, or WordPress can't write to wp-content, it catches crashes after plugins load, and the plugin's page tells you so.
- Every 10 minutes it checks your PHP error logs for new crashes and database errors. WordPress runs scheduled tasks when someone visits the site, so on a quiet site the check waits for the next visit.
- The same crash is emailed at most once every 6 hours, not once per visitor.
- WordPress's own error page and recovery email work as before. Sending the report can delay the error page by up to 3 seconds, at most once per crash every 5 minutes.
- Anything that stops WordPress before it loads: a broken wp-config.php, a database that's down, or a server that's down. For those, the uptime check covers you: once this site is verified, Preventionlabs checks it every 5 minutes, and emails you if the site fails two checks in a row (1 credit a day).
- A crash on a site where alerts were off. The plugin has to be on before the crash.
- A crash on a host that blocks outgoing connections. The error can't be sent.
- Multisite networks. Crash alerts can't be turned on there yet, because every site in a network shares the same crash handler and error logs.
- Pages: errors, slow pages, redirects, pages hidden from Google, broken links, JavaScript errors.
- Security: leaked files such as .env, .git and backups, outdated scripts with known security holes, security headers.
- Uptime and speed: HTTPS, redirects, page weight, caching.
- Search: noindex tags, robots.txt blocks, sitemap pages that fail.
- Email: SPF, DKIM and DMARC, which decide whether your emails land in spam.
- Domain and DNS: DNSSEC, nameservers, records pointing at services that no longer exist.
- WordPress: versions and plugins visible from outside.
安装:
- Install and activate the plugin.
- Sign up at https://app.preventionlabs.com.au.
- In your Preventionlabs dashboard, open Integrations, then AI agents, and click Create API key.
- In WordPress, open Tools > Preventionlabs, paste the key and click Connect.
- Click Verify this site.
- Click Turn on crash alerts, then Send a test email to check alerts reach you.
- Click Run full check.
屏幕截图:
常见问题:
My site shows "There has been a critical error". Can this tell me why?
Only if crash alerts were on before the crash. If your site is down now and you can't log in: open your host's file manager, go to wp-content/plugins, and rename one plugin folder at a time (for example, add -off to the end) until the site comes back. The last one you renamed is the cause. Then turn on crash alerts, so next time you get the answer by email.
Does it slow down my site?
It adds nothing to your pages. The crash catcher only runs when the site crashes; sending the report then can delay the error page by up to 3 seconds, at most once per crash every 5 minutes. The log check runs every 10 minutes in the background and reads only the lines added since the last check.
Will it change how my site handles a crash?
Only by a moment. It sends the error first (taking up to 3 seconds, at most once per crash every 5 minutes), then WordPress handles the crash as usual: the same error page for visitors, and the same recovery email to your admin address.
Why didn't I get an email?
Click Send a test email on the plugin's page. If the test doesn't arrive, check spam or junk, and add alerts@preventionlabs.com.au to your contacts. If the test arrives but crashes don't, check the Crash alerts panel: it says whether the crash catcher is installed and which logs it can read.
Can someone use my key to check other people's sites?
No. A key can only run reports on sites in your account that you've proven are yours. It can't change anything on any site.
Why does verifying fail?
The message says why. The usual causes: a security plugin or firewall blocks the WordPress REST API for visitors (allow /?rest_route=/preventionlabs/v1/proof), the site redirects to another address (check Settings > General), or WordPress runs in a folder such as example.com/blog, which can't prove the whole domain. In those cases, add the DNS record from your Preventionlabs dashboard instead.
What happens when I delete the plugin?
It removes the crash catcher file, the stored key, the proof, the crash alert settings and the last report. Without the proof, the site stops counting as verified at its next report. If you no longer need the key, delete it in your Preventionlabs dashboard too.
更新日志:
- Price wording for Preventionlabs credits: crash alerts use 1 credit a day per site, and the plugin's page says when they're paused for lack of credits.
- Says plainly that crash alerts are part of the Preventionlabs subscription (US$28 a month), and warns on the plugin's page when the account doesn't have it.
- New: crash alerts. When your site crashes, you get an email naming the plugin or theme that broke it, why, and how to fix it.
- Crashes are caught through WordPress's own crash handler, and the PHP error logs are checked every 10 minutes.
- Copyright: Preventionlabs.
- The description says a report takes 15 seconds to about a minute, as the plugin itself does.
- Setup steps say each domain's first 2 full reports are free (new pricing).
- The dashboard page is now called Integrations; instructions updated.
- Copyright notice added.
- Author is now Preventionlabs.
- Verify this site in one click, with no DNS changes.
- First release: connect with an API key, run a full report, copy it.