QoS Reliability History

I have two applications, CircleRx and CircleTx running on two different computers.  CircleRx reads topic Circle, while CircleTx sends one sample of Circle.  CircleRx starts first.  Minutes later CircleTx starts and  immediately sends a single Circle sample.  The sample is sometimes missed by CircleRx.  I suspect this is due to a race condition between discovery and the transmit of the sample.  I assume the Reliabilty QoS can be used to ensure Rx of this sample.  What are the proper Reliability settings  for the reader and writer to ensure deliver

Hello,

My need in a few words is:

• strict reliability
• limited history (N samples)
• non blocking writer

My detailed need:

A late joining reader shall read only the last N written samples. Once these history samples read, the reader shall not lose any sample.

I don't mind if the writer consume as memory as it need to store samples that are not yet acked by the yet connected reader(s).