Problem with Remote Kernels

Questions
1

Hi,

I’ve been strugling to connect my frontend to a remote kernel. Both are version 10 and Linux but the frontend is 32-bits and the kernel 64-bits. Afaik it shouldn’t make a difference but when I ask to evaluate a command it just hangs. Both connections (through both ports) are estabilished and the remote kernel is running and connected but no cigar. The 32/64-bits difference is the only thing I can think of that might be capable of screwing this. I searched everywhere and couldn’t get a straight answer. So any help would be appreciated.

Thanks,
E.

2

The 32 bit / 64 bit is likely not the problem (I can launch from 32 bit windows to 64 bit linux). What method are you using to connect to the remote kernel?

I like to use the RemoteMachine function and explicitly set it the way I need. Here is what I use [note some results/inputs are simulated]:

Needs["SubKernels`RemoteKernels`"]
In[292]:= user = $UserName;
ssh = "\\cygwin\\bin\\ssh";
math = "/usr/local/Wolfram/Mathematica/10.1/Executables/MathKernel" <> 
   " -wstp -linkmode Connect `4` -linkname `2` -subkernel -noinit >&  /dev/null &";
number = 1;
machine = "remotemachine.bigtime.com";
remote = SubKernels`RemoteKernels`RemoteMachine[machine, 
  ssh <> " " <> user <> "@" <> machine <> " \"" <> math <> "\"", number];

In[298]:= remote // InputForm
Out[298]//InputForm=
RemoteMachine["remotemachine.bigtime.com", "\\cygwin\\bin\\ssh bigchad@remotemachine.bigtime.com \
\"/usr/local/Wolfram/Mathematica/10.1/Executables/MathKernel -wstp -linkmode Connect `4` -linkname \
`2` -subkernel -noinit >& /dev/null &\"", 1]

LaunchKernels[remote]
{"KernelObject"[2, "remotemachine.bigtime.com"]}

ParallelEvaluate[$MachineName]
{"remotemachine"}

ParallelEvaluate[3.1/3.21]
{0.965732}

CloseKernels[]
{"KernelObject"[2, "remotemachine.bigtime.com", "<defunct>"]}
3

Hi,

thanks for the answer I’m using almost the same thing except I change both ports used because of firewall problems and tunnel them through ssh. I know it connects because the tunnel I’m using I set the -v option. The only thing different that you use is the -subkernel option but it made no difference, it still hangs. If I kill the kernel process I get a weird message from the frontend ‘the front end encountered an error while processing a “openparallellinkspacket” packet’. I found nothing about it on the internet.

Thanks,

E.

4

I’d suggest talking directly to Tech support at Wolfram so that they can try to exactly match (or come close to it) your configuration.