How to save and replay a trajectory generated with moveit

Hi all, I am using moveit's move_group_interface in C++ to generate a trajectory between two NamedTargets for Youbot. Everything works fine including visualization in RViz. However, on repeated execution, the trajectories look slightly different for the same set of targets. So, my question is: Is there any way one can save a trajectory so that it can be reused later on? I have tried saving the "plan.trajectory_", but it doesn't seem to work. Details of current setup is given below. Robot: Youbot
Planner: OMPL/RRTkConfigDefault
Interface: moveit/move_group_interface in C++
Logic/Sequence Used:
1. Set Start State to Current State
2. Set a Named Target
3. Visualize the plan in Rviz
4. Execute the plan
Thanks