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For DnsBlocklists and URIDNSBL rules (below), you should run a local caching nameserver CachingNameserver on the same machine (or at the least, the same LAN) as the scanner, to increase speed.
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These perform a high number of DNS lookups, so make sure you have a local caching nameserver CachingNameserver, and be prepared to see scan times increase by a second or two on average.
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