Normally, if a host has several A
records, this lookup would return only one, but with the addition of the V8.14 -z switch,
sendmail will return all the entries it finds. Note that when using the -Z dns database-map
switch, if you specify a limit of 2, the successful result will be limited to just two addresses
even if there are more.
23.7.6.3 DNS database-map -z switch
As of V8.14, the -z database-map switch may be used to specify the delimiter that separates
one returned value from the next. For example:
LOCAL_CONFIG
Klookup dns -RA -z,
Here, the lookup database-map will query for an A record. Normally, if a host has several A
records, this lookup would return only one. But with the addition of the V8.14 -z switch,
sendmail will return all the entries it finds, each separated by the character specified, in this
instance the comma:
hostA . example . com , hostB . example . com
Note that if a query will likely return too many entries, you may use the -Z dns databasemap
switch detailed in ?§23.7.6.2 on page 908 to limit the number returned.
23.7.7 hash
A db(3) form of database V8.1 and later
The hash database map type uses a hashing algorithm for storing data. This approach to a
database is described in A New Hash Package for UNIX, by Margo Seltzer (Usenix
This is the Title of the Book, eMatter Edition
Copyright ?© 2007 O??™Reilly & Associates, Inc.
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