PeerBlock is not available for Linux but there are a few alternatives that runs on Linux with similar functionality. The best open source Linux alternative is PeerGuardian. If that doesn't work for you, our users have ranked five alternatives to PeerBlock, but unfortunately only two of them are open source and available for Linux. If you can't find an alternative you can try to remove all filters.
PeerGuardian is a privacy oriented firewall application. It blocks connections to and from hosts specified in huge blocklists (thousands or millions of IP ranges). Its origin seeds in targeting aggressive IPs while you use P2P.
iplist is a Linux application for blocking connections to and from a specified range of hosts using the netfilter netlink-queue library. iplist is an open source IP filtering program similar to PeerGuardian .
Canada
Discontinued but still available, and still an alternative.