On Thu, 26 Mar 2015, Matthew Knepley wrote: > On Thu, Mar 26, 2015 at 2:15 AM, Sanjay Kharche < > sanjay.khar...@manchester.ac.uk> wrote: > > > > > Dear All > > > > I have a fedora pc which some times cannot have an internet connection. I > > found that I can run non-Petsc MPI programs when it is not connected to the > > internet. However, when I try to run my Petsc based program without a > > connection, I get the following error. By googling a little bit, I found > > that the mpi launcher requires to log into each of the 4 procs the pc has, > > and may be using ssh. This or something else may or may not require an > > internet connection. In my present installation of petsc, I have downloaded > > and installed all required dependencies (blas, lapack, sundials) including > > mpich during the configure. I am using a makefile that I took from the ts > > examples for ex15.c where I changed the ex15 entry to sk2d (my program). I > > updated the petsc independent mpich to be the same version as the one I got > > with petsc. > > > > Is there a way of configuring or otherwise to get Petsc programs to run > > when I do not have an internet connection? > > > > the error: > > > > mpiexec -n 3 ./sk2d > > Fatal error in PMPI_Init_thread: Other MPI error, error stack: > > MPIR_Init_thread(498)..............: > > MPID_Init(187).....................: channel initialization failed > > MPIDI_CH3_Init(89).................: > > MPID_nem_init(320).................: > > MPID_nem_tcp_init(171).............: > > MPID_nem_tcp_get_business_card(418): > > MPID_nem_tcp_init(377).............: gethostbyname failed, > > sanjayslaptop.maths.liv.ac.uk (errno 2) > > > > This is not PETSc, but rather the way MPICH is configured. I run using > > -n 3 -hosts localhost,localhost,localhost > > and it will run fine disconnected. > > Satish, is there a general fix?
Presumably non-petsc MPI programs are using a different install of MPI [openmpi?] that doesn't have this problem - so one could install PETSc with that. The other alternative is to configure the laptop/machine to use 'name' that works with gethostbyname() all the time. I do the following: 1. make sure the hostname is in /etc/hostname $ cat /etc/hostname asterix [one is supporsed to use hostnamectl - but I don't really understand this command. soemtimes the hostname is not saved across reboots] 2. Add an entry to /etc/hosts to resolve the set hostname. I have the following entry: 127.0.0.1 asterix Satish > > Thanks, > > Matt > > > > > > cheers > > Sanjay > > > > > >