Chris,
Please read through the above posts by others. yes again.
Keep in mind you are our eyes in this situation.
There are suggestions above and little response from you (like post #21)
Are you using CU 170 on all three IPFire devices?
Pick one device you want to fix. Look for the time of failure and make note of it (for us and for you!)
Look through the logs starting at that time (time of issue) and go backwards about 10 minutes. If you don’t see anything notable, post the message log for entire 10 min time frame. (make sure we know what time it failed).
Same for the OpenVPN log.
Look through the graphs (like Memory). Look at the same time. Did it spike again?