does this help?
https://support.symantec.com/en_US/article.PROD1555.html
SSLV Offload
In this release, you can connect one or more ProxySG appliances to an SSL Visibility appliance running version 4.0.1 to offload SSL/TLS traffic processing. Configuring SSLV offload requires that you identify the ProxySG and SSLV appliances to each other using their respective serial numbers.
Configure SSLV offload on the ProxySG appliance using one of the following methods:
- Managing SSLV appliances in the Management Console (Configuration > SSL > SSLV Offload)
- Issuing the #(config ssl)sslv-offload command
You must also add ProxySG appliance information to the SSLV appliance(s).
explaination on SSl offload config
https://symwisedownload.symantec.com//resources/sites/SYMWISE/content/live/DOCUMENTATION/9000/DOC9832/en_US/Reverse_Proxy_with_SSL.b.pdf?__gda__=1501008628_6c6308a149563b13f0a7363d0b1f831c