Multiple Pointer Records
While most rDNS entries only have one PTR record, DNS does not restrict the number. However, having multiple PTR records for the same IP address is generally not recommended, unless there is a specific need. For example, if a web server supports many virtual hosts, there may be one PTR record for each host and some versions of name server software will allocate this automatically. Multiple PTR records can cause problems, however, including triggering bugs in programs that only expect single PTR records and, in the case of a large web server, having hundreds of PTR records can cause the DNS packets to be much larger than normal.
Read more about this topic: Reverse DNS Lookup
Famous quotes containing the words multiple, pointer and/or records:
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—Faye J. Crosby (20th century)
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—Ralph Waldo Emerson (1803–1882)
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