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Check if a server IP is on the Spamhaus blacklist

harmlessDNSdebian, ubuntu
Adjust the values, the command updates live
user@server
dig +short $(echo 203.0.113.10 | awk -F. '{print $4"."$3"."$2"."$1}').zen.spamhaus.org

Reverses the IPv4 address and looks it up as a name in the zen.spamhaus.org zone. No output means not listed, an answer in the 127.0.0.x range indicates a listing, and the last number reveals the list (for example 2 for SBL, 4 for XBL). Listed IPs are rejected outright by many mail servers.

Note: Spamhaus does not answer queries sent through large public resolvers and returns 127.255.255.254 instead. The lookup must go through your own resolver.

Also searched as

  • is my server ip blacklisted
  • emails rejected because of spamhaus
  • check ip against rbl

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