Справочник Пользователя для Blue Coat Systems Time Clock Proxy SG
Chapter 4: Property Reference
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ttl( )
Sets the time-to-live (TTL) value of an object in the cache, in seconds. Upon expiration, the cached
copy is considered stale and will be re-obtained from the origin server when next accessed. However,
this property has an effect only if the following HTTP command line option is enabled
copy is considered stale and will be re-obtained from the origin server when next accessed. However,
this property has an effect only if the following HTTP command line option is enabled
:
Force
explicit expirations: Never serve after.
If the above option is not set, the ProxySG’s freshness algorithm determines the time-to-live value.
Note:
advertisement(yes)
overrides any
ttl( )
value.
Syntax
ttl(seconds)
where
seconds
is an integer, specifying the number of seconds an object remains in the cache before it
is deleted. The maximum value is 4294967295, or about 136 years.
The default value is specified by configuration.
Layer and Transaction Notes
•
Use in
<Cache>
layers.
•
Do not use in
<Proxy>
layers.
Example
; Delete the specified cached objects after 30 seconds.
url=//www.example.com/dyn_images ttl(30)
See Also
•
Properties:
advertisement( )
,
cache( )