DD9500 - OS:5.7.7 - DDBoost : Allowed client list vs ifgroup

Hello Experts,

            Our Netbackup servers have two different Networks, one for management(front_end - 1G) & one for data transfer(back_end - 10G).

During our initial set up, we created a storage-unit and added the Netbackup servers IP(back_end) to the allowed client list. The backup server couldn't authenticate itself and failed to connect, next we added the Netbackup management IP(front_end) to the allowed client list which worked. Now the allowed client list has both front_end & back_end IPs.

I want to understand what DD uses to authenticate it's clients and if all back_end/front-end IPs should be added to the allowed client list.

Allowed client list  - Add both front_end & back_end IPs

Interface Groups - Add only back_end for data transfer (will nebackup be able to connect if I directly add back_end interfaces to the DD ifgroups bypassing the allowed client list). What is the max number of hosts that can be in an interface group

I did read a lot of documentation but got into a confused state when I was give two different networks from our Netbackup folks.

Also, how do I verify if "system.ENFORCE_IFGROUP_RW=TRUE" is set.

pleases note:My understanding is a bit naive with DD.

Appreciate all your support.

Thanks