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When you have an RRSET (resource record set) that contains different TTL settings for each record, Grid Manager displays the actual TTL values for these records. However, in DNS responses, the appliance takes the least of the values and returns that as the TTL setting for all resource records in the RRset.
For recursive DNS seversservers, you can specify the maximum cache TTL value that establishes the time limit for the name server to cache positive responses. You can also specify the maximum negative cache TTL value that specifies the time limit for the name server to cache negative responses. For information about how to configure these settings, see Specifying Max Cache TTL and Max Negative Cache TTL Settings below.
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