This optional parameter specifies how the pool hint is
derived. A pool hint is generally used by an AddressAllocator to determine
which pool to allocate an address from. The value of the pool hint will
therefore depend on what type of Address Allocator you are using, and
usually which pools are available.
The default PoolHint (and the
most common requirement) is ‘%{Reply:PoolHint}’, which means the pool hint
is an attribute called ‘PoolHint’ in the current reply. Presumably the
PoolHint will have been set in the reply by some previous AuthBy clause.
This is easy to do for example in an AuthBy FILE, by adding the pool hint
attribute to the users file:
user1 Password=x
PoolHint=pool1
user2 Password=y
PoolHint=pool2
The PoolHint attribute will then be
used by the Address Allocator to indicate which pool to allocate from. The
exact way the pool hint is used depends on the type of Address Allocator
you are using, so refer to the documentation for the Address
Allocator.
Tip
If the pool hint resolves to an empty
string, a DEBUG message will be issued, no address will be allocated, but
the request will be ACCEPTED. This allows you to arrange for only some
users to get an address allocated (and the NAS will allocate addresses for
the others).