Edge Cache Configuration

When web objects are downloaded from the Internet or across WAN links, Edge Cache stores them at the edge of the network. When subsequent requests come for the same material, the content is quickly delivered from the Edge Cache without the need to download the data again over the WAN. Edge Cache can cache web objects, videos, software updates, and other content on the WAN. You can control whether to exclude particular sources, or sizes of objects from being cached. The cache objects can also be shared among peer appliances if desired, meaning that if the content cannot be found in the cache of the appliance through which the traffic is passing, then the appliance can request the content from peer appliances. You are also able to clear the cache, if desired.

To learn the details of how edge cache works, see How Edge Cache Works or to learn all the details of how to configure Edge Cache including configuring DNS and HTTPS certificates and blacklists and whitelists, see the Edge Cache.

You may want to limit the size of objects that can be cached. Since the cache storage size is limited, you may want to decide whether to allow a few large objects or lots of little objects. You should ensure that the size is aligned with the types of objects that you want to be cached. For example, iOS updates tend to be approximately 1 GB and Mac updates tend to be 6 GB and so if you want Edge Cache to help with caching of these updates, you'll want to ensure that the minimum and maximum allowed objects size accommodates these sizes.

You may want to blacklist particular sites if Edge Cache is not working properly and is preventing the network user from getting access to the site. Also, you may want to blacklist secure sites because you do not want to cache sensitive data such as financial or banking sites. Alternatively, if you want to only cache particular secure sites once they've been identified as important to your network, you can whitelist them such that only those sites listed will be cached. Whitelisting is only available for HTTPS caching. You can specify your whitelist and blacklist as source IP, destination IP, source domain, or destination domain. Domains are resolved using the DNS.

To use HTTPS caching, you will need to specify which signing certificate will be used by Edge Cache to generate a certificate to negotiate with the client on behalf of the server.


For versions prior to 7.0.2, Edge Cache requires you to restart the Edge Cache process after making any modifications to the Edge Cache configuration. With 7.0.2 and later, the Edge Cache process automatically restarts when needed.


Objects in the traffic that are matched with an Edge Cache policy but are excluded from storage in Edge Cache due to these settings, will still pass through Edge Cache unprocessed and will be highlighted on the Real Time conversations screen in blue (indicating that they passed through and were evaluated by Edge Cache).