In Part 1 and Part 2 of this series we covered what blacklists are, how they're built, and how mail administrators use them to filter traffic. Here we'll look at how a listing actually affects your organization and why it's worth paying attention to.
Why Should I Care?
Getting listed on a blacklist (RBL or URIBL) is not uncommon. It happens to organizations of all sizes, often for reasons outside their direct control:
- A customer using your email platform sent bulk mail in violation of your terms.
- An employee downloaded malware that started spamming their contact list.
- A misconfigured mail server opened your infrastructure as an open relay.
- A compromised CMS installation injected phishing code into your site.
Everyone makes mistakes. As a mail recipient, blacklists protect you by rejecting suspect messages before they reach your inbox. As a sender, getting listed limits the damage from a compromise and reduces your overall liability by cutting off the flow of malicious traffic originating from your infrastructure.
What Happens When You're Listed?
Once listed, a significant portion of your outbound email won't reach its destination, and web traffic to flagged domains can be blocked by DNS security filters. If your business depends on email, every hour you remain listed affects your bottom line and your reputation.
Customers who email you and receive a bounce message indicating your mail server has been blocked is a bad look. The sooner you know there's a problem, the sooner you can fix it and request delisting. Our guide to getting delisted walks through the process step by step.
Monitoring Is the Key
Automated blacklist monitoring checks your IP addresses and domains continuously against the major DNSBLs and alerts you immediately if anything gets listed. Generator Labs provides this monitoring as a core service, so you can catch issues before they turn into a real problem for your business or your customers.