Ah, yes - that pinpoints the problem. It looks like your vpn is indeed interfering with connections. I suspect it must be some kind of vpn/Ubuntu configuration issue as I have the same experience on my Mac laptop that you report (i.e., no issue).
I'd suggest googling the Ubuntu site (or just in general) to see if someone has a suggestion. Afraid I'm not a Ubuntu nor vpn person and don't have an immediate answer. :-( FWIW: it isn't a specific connection - we just ask for any port and use the standard Linux "connect" function. On Mar 22, 2013, at 5:12 AM, David A. Boger <dab...@psu.edu> wrote: > Following up on your TCP remark, I found that during the delay, netstat -tnp > shows > > tcp 0 1 192.168.1.3:56343 192.168.1.3:47830 SYN_SENT > 24191/mpi_hello > > and that while the vpn is connected, I am unable to ping 192.168.1.3 (the > machine I am on). > > On the other hand, on the laptop (where mpi runs fine with vpn connected), > the ping-to-self works fine even when the vpn is connected. > > > > > On Fri, Mar 22, 2013 07:37 AM, "David A. Boger" <dab...@psu.edu> wrote: > Thanks Ralph. I have a Mac OS X 10.6.8 laptop where I can run open-mpi 1.2.8 > and open-mpi 1.6.4 with the vpn connected without any problem, even without > having to exclude the vpn interface, so you're probably right -- the > existence of the vpn interface alone doesn't explain the problem. > Nevertheless, disconnecting the vpn on my ubuntu box definitely resolves the > problem, so I think it's tied in somehow. > > Do you think the process is hanging looking for a specific TCP connection, or > just any TCP connection? If it's a specific one, is there a way to find out > which or to test using something outside of mpirun that would show the same > delay? > > Thanks again, > David > > On Fri, Mar 22, 2013 12:25 AM, Ralph Castain <r...@open-mpi.org> wrote: > The process is hanging trying to open a TCP connection back to mpirun. I would > have thought that excluding the vpn interface would help, but it could be that > there is still some interference from the vpn software itself - as you > probably > know, vpn generally tries to restrict connections. > > I don't recall seeing this behavior with my laptop (which also runs with a > Cisco vpn), but I'll check it again in the morning and let you know. > > > On Mar 21, 2013, at 6:52 PM, David A. Boger <dab...@psu.edu> wrote: > > > I am having a problem on my linux desktop where mpi_init hangs for > approximately 64 seconds if I have my vpn client connected but runs > immediately > if I disconnect the vpn. I've picked through the FAQ and Google but have > failed > to come up with a solution. > > > > Some potentially relevant information: I am using Open MPI 1.4.3 under > ubuntu 12.04.1 and Cisco AnyConnect VPN Client. (I have also downloaded > openmpi 1.6.4 and built it from source but believe it behaves the same > way.) > > > > Some potentially irrelevant information: I believe SSH tunneling is > disabled by the vpn. While the vpn is connected, ifconfig shows an extra > interface (cscotun0 with inet addr:10.248.17.27 that shows up in the > contact.txt file: > > > > wt217:~/wrk/mpi> cat > /tmp/openmpi-sessions-dab143@wt217_0/29142/contact.txt > > 1909850112.0;tcp://192.168.1.3:48237;tcp://10.248.17.27:48237 > > 22001 > > > > The code is simply > > > > #include <stdio.h> > > #include <mpi.h> > > > > int main(int argc, char** argv) > > { > > MPI_Init(&argc, &argv); > > MPI_Finalize(); > > return 0; > > } > > > > I compile it using "mpicc -g mpi_hello.c -o mpi_hello" and > execute it using "mpirun -d -v ./mpi_hello". (The problem occurs > whether or not I asked for more than one processor.) With verbosity on, I > get the following output: > > > > wt217:~/wrk/mpi> mpirun -d -v ./mpi_hello > > [wt217:22015] procdir: /tmp/openmpi-sessions-dab143@wt217_0/29144/0/0 > > [wt217:22015] jobdir: /tmp/openmpi-sessions-dab143@wt217_0/29144/0 > > [wt217:22015] top: openmpi-sessions-dab143@wt217_0 > > [wt217:22015] tmp: /tmp > > [wt217:22015] [[29144,0],0] node[0].name wt217 daemon 0 arch ffc91200 > > [wt217:22015] Info: ! Setting up debugger process table for applications > > MPIR_being_debugged = 0 > > MPIR_debug_state = 1 > > MPIR_partial_attach_ok = 1 > > MPIR_i_am_starter = 0 > > MPIR_proctable_size = 1 > > MPIR_proctable: > > (i, host, exe, pid) = (0, wt217, > /home/dab143/wrk/mpi/./mpi_hello, 22016) > > [wt217:22016] procdir: /tmp/openmpi-sessions-dab143@wt217_0/29144/1/0 > > [wt217:22016] jobdir: /tmp/openmpi-sessions-dab143@wt217_0/29144/1 > > [wt217:22016] top: openmpi-sessions-dab143@wt217_0 > > [wt217:22016] tmp: /tmp > > <hangs for approximately 64 seconds> > > [wt217:22016] [[29144,1],0] node[0].name wt217 daemon 0 arch ffc91200 > > [wt217:22016] sess_dir_finalize: proc session dir not empty - leaving > > [wt217:22015] sess_dir_finalize: proc session dir not empty - leaving > > [wt217:22015] sess_dir_finalize: job session dir not empty - leaving > > [wt217:22015] sess_dir_finalize: proc session dir not empty - leaving > > orterun: e! xiting with status 0 > > > > The code hangs for approximately 6! 4 second s after the line that reads > "tmp: /tmp". > > > > If I attach gdb to the process during this time, the stack trace > (attached) shows that the pause is in __GI___poll in > /sysdeps/unix/sysv/linux/poll.c:83. > > > > If I add "-mca oob_tcp_if_exclude cscotun0", then the > corresponding address for that vpn interface no longer shows up in > contact.txt, > but the problem remains. I also add "-mca btl ^cscotun0 -mca > btl_tcp_if_exclude cscotun0" with no effect. > > > > Any idea what is hanging this up or how I can get more information as to > what is going on during the pause? I assume connecting the vpn has caused > mpi_init to look for something that isn't available and that eventually times > out, but I don't know what. > > > > Output from ompi_info and the gdb stack trace is attached. > > > > Thanks, > > David > > > > > <stack.txt.bz2><ompi_info.txt.bz2>_______________________________________________ > > users mailing list > > us...@open-mpi.org > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users