We monitor several backup services that send emails about their status just as described in the article How can I monitor my backup software to be sure backup succeeded last night?. For the sensor to show an error as soon as a backup failed, we use regular expressions in the search text field. If the email body does not contain “Failed Backups: 0” (but a number bigger than 0), for example, we want the sensor to show an alarm.
For plain text emails, this works as expected. However, some solutions send HTML emails. The IMAP sensor obviously recognizes these emails but erroneously changes to a Down status even if the regex in the search text field does match the "successful backup" condition.
The sensor log shows that the sensor seems to analyze only a part of the HTML emails. Is there any solution to this issue?