DHCP option 43 suboption 8 to provide proxy server information in phone-home client

During the bootstrapping process, the phone-home client (PHC) can access the redirect server through a proxy server. The DHCP server uses DHCP option 43 sub option 8 to deliver the details of IPv4 and/or IPv6 proxy servers to the PHC. The DHCP daemon running on the target switch learns about the proxy servers in the initial DHCP cycle and then populates either the phc_vendor_specific_info.xml files or the phc_v6_vendor-specific_info.xml files located in the /var/etc/ directory with the vendor-specific information.