Citrix has released a tool that can help you migrate from a Cisco ACE solution to NetScaler. Citrix Netscaler is the recommended replacement product for Cisco ACE according to Cisco themselves (see https://www.citrix.com/products/netscaler-application-delivery-controller/overview/cisco-ace.html for additional details).
With the ACE Migration Tool now available in the Citrix Insight Services platform, converting your existing ACE configuration files to NetScaler configuration files takes only seconds.
Begin by gathering up your Cisco ACE configuration files. Please note that this tool converts one ACE virtual context configuration file to a dedicated NetScaler instance. This doesn’t support converting all ACE virtual contexts at one time to a NetScaler configuration that uses our other forms of virtualization: Traffic Domains and Admin Partitions. For example, to migrate from the Cisco ACE-4710 with 4 virtual contexts to a NetScaler SDX, you’ll need to use the tool for each individual virtual context on ACE, then copy the converted configuration in to each of the 4 VPX instances running on the NetScaler SDX. A manual approach is necessary to merge the ported NetScaler configs in to one that supports Traffic Domains and/or Admin Partitions.
Go to http://cis.citrix.com to learn more (requires a valid mycitrix.com account!)