******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hello Nektar, I am unable to restart a simulation after moving the case files to a new cluster. I began the simulation on one cluster and ran it to the end of the transient flow stage. Once finished, took the final .fld file, put it on another cluster and tried to run it from that time step. My expansion section is <EXPANSIONS> <F VAR="u,v,w,p" FILE="session.fld" /> </EXPANSIONS> and my initial conditions are <FUNCTION NAME="InitialConditions"> <F VAR="u,v,w,p" FILE="session.fld" /> </FUNCTION> When I try to start the simulation on the new cluster, I get the same CG iterations problem every time (see output file as text at the bottom of this email). The new cluster uses different CPUs, so I thought this could have something to do with it, but I am still getting the same problem when I try different CPUs. The only thing I tried which had any effect was changing the time step size. This shouldn't have been necessary because the one I was using was already keeping the CFL low (~0.5) during the transient flow. Decreasing CFL only lowered the size of the error on the CG iterations made... line displayed before the Level 0 assertion violation, and not by much. I would be grateful for your assistance. Regards, Isaac ======================================================================= EquationType: UnsteadyNavierStokes Session Name: session Spatial Dim.: 3 Max SEM Exp. Order: 5 Num. Processes: 208 Expansion Dim.: 3 Projection Type: Continuous Galerkin Advect. advancement: explicit Diffuse. advancement: implicit Time Step: 0.004 No. of Steps: 187500 Checkpoints (steps): 63 Integration Type: IMEX Splitting Scheme: Velocity correction (strong press. form) Dealiasing: spectral/hp Smoothing-SpecHP: SVV (spectral/hp DG Kernel (diff coeff = 1*Uh/p)) ======================================================================= Initial Conditions: - Field u: from file session.fld - Field v: from file session.fld - Field w: from file session.fld - Field p: from file session.fld CG iterations made = 5001 using tolerance of 1e-09 (error = 9.57894e-07, rhs_mag = 15.6227) Fatal : Level 0 assertion violation Exceeded maximum number of iterations -------------------------------------------------------------------------- Primary job terminated normally, but 1 process returned a non-zero exit code. Per user-direction, the job has been aborted. -------------------------------------------------------------------------- -------------------------------------------------------------------------- mpiexec detected that one or more processes exited with non-zero status, thus causing the job to be terminated. The first process to do so was: Process name: [[2602,1],4] Exit code: 1 --------------------------------------------------------------------------