cedric knight greennet oovhetgnapcorg noel jones wrote cedric knight greennet wrote way look reverse_name table instead limiting verified hostnames postfix doesnt check_reverse_client_access lookup unverified hostnames cant used safely whitelisting use write policy server rejects clients based reverse hostname believe policyd ability along many others httpwwwpostfixorgsmtpd_policy_readmehtml httpwwwpostfixorgaddonhtmlpolicy httppolicydsourceforgenet patch source code add new lookup type particular mod looks fairly easy thanks makes options clear fact one purposes preventing connections getting far policy stage case gps greylisting avoiding relatively cpuintensive database lookups maybe ill request feature meantime may break banned hostnames ip24 blocks ck wed 06 aug 2008 023518 0000 access table unverified hostnames