IP from QName filter

Note: The IP from QName filter is only available upon request. Contact IBM support for details.

The "IP from QName" traffic steering filter extracts the IPv4 address embedded in the query name (QName) of the requestor. Subsequent filters in the Filter Chain — that is, traffic steering filters that are positioned after the IP from QName filter — use the extracted IP address to inform the way they process incoming queries. For example, geographic-based traffic steering filters use this IP address to determine the geographic location of the requester. If the QName is ipv4.192.0.2.1.example.com or ipv4-192-0-2-1.example.com, the filter recognizes 192.0.2.1 as the requester IP address.

The extracted IP address is also used by Filter Chains attached to other records linked to this record via CNAME reference. The format of the extracted IP address is as follows:

( $qname =~ /^ipv4\.([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)\.(.*)$/ || $qname =~ /^ipv4\-([0-9]+\-[0-9]+\-[0-9]+\-[0-9]+)\.(.*)$/ ).

The order of the filters in a Filter Chain determines the logical processing order of incoming queries to the record on which the Filter Chain is applied. Ensure you place the this filter ahead of the geographic or fencing filters so they can reference the extracted IP address.

Note: The IP from QName filter extracts IPv4 addresses only and ignores the "Enable client subnet" option within the Filter Chain configuration.