cRIO Time-Synchronization NTP when cRIO is offline

All

I am trying to synchronize my cRIO to a NTP server that is hosted on an accessible intranet but no access to internet. I was looking at 

https://forums.ni.com/t5/Example-Code/Installing-and-Configuring-NTP-on-NI-Linux-Real-Time-Devices/ta-p/3529606?profile.language=en

I was going to download the opkg package offline from https://downloads.openwrt.org/releases/, and transfer via USB to the cRIO and install.

It looks like opkg is target dependent. It looks like cRIO 9045 is armv7, but how do I match that with the compatible targets for opkg? Thoughts?