Intel 1520 Manuale Utente

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Intel NetStructure Cache Appliance Administrator’s Guide
The following table shows the options:
Option 
Description 
Options to Verify freshness
Choosing this option lets you configure how 
the appliance asks the original content server 
to verify the freshness of objects (revalidate 
them) before serving them. 
Select from one of the following options and 
press Enter. After pressing Enter press 
CTRL-X to save your changes and return to 
the previous screen.
When The Object Has Expired—The 
appliance revalidates objects with explicit 
expiration dates after they expire. 
Otherwise, it uses heuristic methods to 
evaluate freshness and revalidates the 
object should it be stale.
When The Object Has Expired Or Has No 
Expiry Date—The appliance revalidates 
objects with explicit expiration dates after 
they expire. All other documents are 
revalidated before serving. 
Always—The appliance always revalidates 
objects before serving them. 
Never—The appliance never checks object 
freshness. 
Freshness information 
Specifies the minimum freshness information 
required when considering to cache a 
document. 
Select from one of the following options and 
press Enter. After pressing Enter press 
CTRL-X to save your changes and return to 
the previous screen.
An Explicit Lifetime—The appliance only 
caches objects with 
Expires
 headers or 
Cache-Control: max-age
 headers. 
A Last Modified Time—The appliance only 
caches objects with 
Expires
 headers, or 
Cache-Control: max-age headers
or 
Last-Modified
 headers. 
Nothing—The appliance caches 
documents regardless of freshness 
headers.