# Restarting using gro file **URL:** \ **Category:** User discussions\ **Created:** [December 21, 2020, 1:14pm UTC](https://gromacs.bioexcel.eu/t/restarting-using-gro-file/1301 "2020-12-21T13:14:14Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![mjm91](https://avatars.discourse-cdn.com/v4/letter/m/54ee81/32.png) [@mjm91](https://gromacs.bioexcel.eu/u/mjm91)\ **Post date:** [December 21, 2020, 1:14pm UTC](https://gromacs.bioexcel.eu/t/restarting-using-gro-file/1301/1 "2020-12-21T13:14:14Z")
GROMACS version: 2018 GROMACS modification: No Here post your question Hi, I would like to extend a previously run 10 ns simulation by another 10 ns. I have mistakenly deleted the checkpoint file. Is it possible to continue the simulation using the final gro file generated from the first 10 ns mdrun? Generating a tpr file using the same mdp parameters and final gro file from previous 10 ns, can extend the earlier 10 ns to get a 20 ns trajectory after possible concatenation ---
**Author:** ![alevilla](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/alevilla/32/439_2.png) [@alevilla](https://gromacs.bioexcel.eu/u/alevilla)\ **Post date:** [December 21, 2020, 5:35pm UTC](https://gromacs.bioexcel.eu/t/restarting-using-gro-file/1301/2 "2020-12-21T17:35:09Z")
Hi, To generate a new run, you can generate a new tpr using the gro file of the last frame (having both coordinates and velocities). If you want you can change the starting time and put gen\_vel = no in the mdp file. In such a way you will start from the last sampled point of the phase space Best regards Alessandra ---
**Author:** ![mjm91](https://avatars.discourse-cdn.com/v4/letter/m/54ee81/32.png) [@mjm91](https://gromacs.bioexcel.eu/u/mjm91)\ **Post date:** [December 22, 2020, 5:09am UTC](https://gromacs.bioexcel.eu/t/restarting-using-gro-file/1301/3 "2020-12-22T05:09:27Z")
Thank you Alessandra for your suggestion