load balancing
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...
Weight
Load balancing mechanism. When selecting a target host among
the those that have the same priority ...
... Domain administrators are urged to use
Weight 0 when there isn't any load balancing to do, to make the
RR easier to read for humans (less noisy).
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Weight, the load balancing field, is not quite satisfactory, but the
actual load on typical servers changes much too quickly to be kept
around in DNS ...
... Brisco, T., "DNS Support for Load Balancing", April 1995. ...