After you add a domain name to Alibaba Cloud CDN, we recommend that you set a cache expiration time, set a bandwidth cap, and configure HTML optimization. These features increase the cache hit ratio, reinforce security, and improve content retrieval efficiency.
Increase the cache hit ratio and accelerate content delivery
|The cache hit ratio is low and content retrieval is slow||The (time-to-live) TTL value for cached content is smaller than required or no cache
expiration rule is created, which causes requests to be frequently redirected to the
origin server. Set a proper TTL value to increase the cache hit ratio and accelerate
We recommend that you set a TTL value based on the following rules:
|Add a cache rule|
|By default, client requests are redirected to the origin server with the complete
URLs retained, including parameters that follow the question mark (
For more information about causes of low cache hit ratios, see Causes of low cache hit ratios.
Improve service security
|Prevent high bandwidth values||You can set a bandwidth cap. If a bandwidth value during a statistical period exceeds the bandwidth cap, Alibaba Cloud CDN suspends acceleration and disables the accelerated domain name. All requests that are destined for the accelerated domain name are directed to the origin server.||Set a bandwidth cap|
|You can set alert rules in CloudMonitor to monitor bandwidth values. This allows you to detect and manage bandwidth anomalies at the earliest opportunity.||Set an alert rule|
Improve service performance
|Clients retrieve specified file chunks from the origin server. In scenarios such as large file distribution, the amount of back-to-origin traffic can be reduced and content retrieval efficiency can be improved.||Object chunking|
|CDN nodes use Gzip to compress text files before they are returned to users. This reduces the size of the requested files, accelerates content delivery, and reduces bandwidth usage.||Configure intelligent compression|