> For the complete documentation index, see [llms.txt](https://docs.lightningrails.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lightningrails.com/deploying-to-production/security/error-monitoring-with-sentry.md).
# Error Monitoring with Sentry
Sentry is a powerful error tracking tool that helps you monitor and fix crashes in real-time. Adding it to your Lightning Rails project gives you instant visibility into production issues with stack traces, request context, and more.
### Installation
The Sentry SDK for Rails comes as two gems. Add them to your `Gemfile`:
```ruby
gem "sentry-ruby"
gem "sentry-rails"
```
Then install the gems:
```bash
bundle install
```
***
### Configure SDK
Generate the initializer with:
```bash
rails generate sentry
```
This creates `config/initializers/sentry.rb`.
Now edit the generated file to include your configuration:
```ruby
if Rails.env.production?
Sentry.init do |config|
config.dsn = 'https://8f1bc0b22a55bb483283e664f9fb421f@o4509708042043392.ingest.us.sentry.io/4509789067608064'
config.breadcrumbs_logger = [:active_support_logger, :http_logger]
# Add data like request headers and IP for users,
# see https://docs.sentry.io/platforms/ruby/data-management/data-collected/ for more info
config.send_default_pii = true
end
end
```
> π‘ Make sure to only enable this in production by wrapping it in `if Rails.env.production?` , we don't want to spam our email with error messages when developing ;)
***
### Verify Itβs Working
You can test the setup by triggering a sample error in the production console.
```ruby
begin
1 / 0
rescue ZeroDivisionError => exception
Sentry.capture_exception(exception)
end
Sentry.capture_message("test message")
```
This should send both the exception and the message to your Sentry dashboard.
***
### Optional: Trace Propagation (Frontend + Backend)
If you're using frontend Sentry, you can enable distributed tracing by leaving this in your layout:
```erb
<%= Sentry.get_trace_propagation_meta.html_safe %>
```
It should have been added to your header when you used the generator above. `` tag in `app/views/layouts/application.html.erb`.
Happy Bug Tracking! ππ¦π·οΈπͺ²
---
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