Install libnet-rblclient-perl by entering the following commands in the terminal:
sudo apt update sudo apt install libnet-rblclient-perl
module to query multiple Realtime Blackhole Lists in parallel
The Net::RBLClient module is used to discover what RBL's are listing a particular IP address. It parallelizes requests for fast response. . An RBL, or Realtime Blackhole List, is a list of IP addresses meeting some criteria such as involvement in Unsolicited Bulk Email. Each RBL has its own criteria for addition and removal of addresses. If you want to block email or other traffic to/from your network based on one or more RBLs, you should carefully study the behavior of those RBLs before and during such blocking.