Bot detection

elmah.io can help you with classifying log messages generated by bots and crawlers. When storing a log message, we run a range of checks to try and identify if a log message is generated by an automated script or a real human visitor of your website/application. In this case, a flag named isBot is set to true on the message. In case we couldn't identify a log message as generated by a bot, the flag is set to false.

Besides an automated check, you can also mark a log message as generated by a bot manually. This is done from within the elmah.io UI:

Mark message as bot

The benefit of marking log messages with the isBot flag manually is that elmah.io will then automatically mark new instances of this log message with isBot=true (this feature is available for automatically bot-marked log messages as well). By doing so you get the possibilities listed later in this article.

Log messages marked as generated by bots include a small robot icon on the search result:

Bot messages result

Search by or not by bots

If you want to show all log messages generated by bots you can create a search query like this:

isBot:true

Or include a search filter for the Is Bot field:

Is Bot filter

By reversing the filter, you see a list of log messages NOT generated by a bot, which can make it easier to get an overview of "real" errors.

Hide or ignore log messages generated by bots

By using the isBot field in Hide and Ignore filters, you can let elmah.io automatically hide or ignore future log messages generated by bots. Be aware that creating ignore filters based on the isBot field is only available for users on the Enterprise plan.

To create a new filter, navigate to the Rules tab on log settings, and click the Add a new rule button. Input a query including the isBot field and select either the Hide or Ignore action:

Is Bot rule

Mark log messages using rules

It is possible to automatically mark log messages using rules. If you know that an IP range or a specific user agent is a bot, setting up a Mark as bot rule can be done from either log search or log settings:

Mark as bot rule


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