DNS Blacklist Monitoring
Catch your mail server on a spam blacklist before your email stops arriving.
A DNSBL monitor checks whether an IP — or a hostname's IP — is listed on public spam blacklists, using the same DNS lookups mail servers rely on.
What it detects
- Listings on the blacklists you choose (a well-known default set otherwise)
- How many lists include the IP, against a threshold you set
- Blacklists that didn't answer — reported separately, never counted as “clean”
How you're alerted
- The monitor goes down once the listing threshold is reached.
Notifications go to any of 8 channels — see notifications.
- Runs from
- MonSPHERE's own workers — no region to pick
- Address family
- IPv4
- Available on
- Free, Professional · Enterprise and Custom on request
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Start monitoring everything in minutes
Create a free account, add your first check and get alerted the moment something breaks — no credit card required.