Introduced : BIG-IP_v11.3.0
Sets whether to randomly vary the case of letters in domain names queried for a set of DNS caches. If disabled, the resolver will not vary the case of letters in domain names queried. The DNS standards require that nameservers treat query names case-insensitively. Domain names with the same letter, regardless of the case, should resolve to the same IP address. On the other hand, for the response, nameservers should preserve the original case that appeared in the request. This technique will help to reduce the risk of cache poisioning.


    in String [] caches,
    in EnabledState [] states


Parameter Type Description
caches String [] Names of the caches to modify.
states EnabledState [] Whether to vary the case of letters in domain names for a set of caches.

Return Type

Type Description


Exception Description
Common::AccessDenied Raised if the client credentials are not valid.
Common::InvalidArgument Raised if one of the arguments is invalid.
Common::OperationFailed Raised if an operation error occurs.

See Also


The links to the sample code below are remnants of the old DevCentral wiki and will result in a 404 error. For best results, please copy the link text and search the codeshare directly on DevCentral.

Sample Code

The BIG-IP API Reference documentation contains community-contributed content. F5 does not monitor or control community code contributions. We make no guarantees or warranties regarding the available code, and it may contain errors, defects, bugs, inaccuracies, or security vulnerabilities. Your access to and use of any code available in the BIG-IP API reference guides is solely at your own risk.