How can I convert GMSH meshs to OGS meshs with the tool GMSH2OGS?

Dears
Hi
Please help me How can I convert GMSH meshs to OGS meshs with the tool GMSH2OGS?

Best Regards

After having generated the mesh with GMSH, go to menu File >> Export >> set the filename to something.msh, click save and then a pop-up window will appear, where you must choose the mesh format “Version 2 ASCII”
.

Dear Lurpi,
Really appreciate for your suggestion.
In fact, I can generated the GMSH mesh with the mesh format “Version 2 ASCII”. What I really want to know is how to transform the mesh with the format “Version 2 ASCII” to the mesh that OGS can read.
As far as I know ,OGS can not read the mesh with the format “Version 2 ASCII” directly.
Best wishes,
Wang_J

If you are referring to OGS6, to generate the vtu mesh premesh.vtu that can be visualized in Paraview starting from the GMSH mesh output.msh:
GMSH2OGS -i output.msh -o premesh.vtu -e
and for this vtu to be used in OGS6 best to check the order of the nodes:
NodeReordering -i premesh.vtu -o ogs_mesh.vtu -m 1

The file ogs_mesh.vtu is then ready to be used in your numerical model.

Please note that the mesh domain of interest must be defined as Physical surface/volumes in GMSH.

If you need to convert for OGS5, I am not familiar with the GMSH2OGS tool of OGS, but you can try to use some scripts I created for my own use (read: no guarantee on them, no manual or documentation available):

Dear Lurpi,
Really appreciate for your suggestion.My problem has been solved.
Best wishes,
Wang_J

Dear Wang-J
I also face this problem ,would you share the detail operation steps with me?
Best Regards
Rui Tang

What is your exact problem?
The answer was given by lurpi quite in detail.
You can also try msh2vtu (https://github.com/dominik-kern/msh2vtu) to convert meshes.
This allows you also to extract boundary meshes from physical groups.