1. fast alternative to apache logresolve The jdresolve application resolves IP addresses into hostnames. To reduce the time necessary to resolve large batches of addresses, jdresolve opens many concurrent connections to the DNS servers, and keeps a large number of text lines in memory. These lines can have any content, as long as the IP addresses are the first field to the left. This is usually the case with most formats of HTTP and FTP log files. From Debian 3.0r0 APT