Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |  

This web mail archive is frozen.

This page is part of a frozen web archive of this mailing list.

You can still navigate around this archive, but know that no new mails have been added to it since July of 2016.

Click here to be taken to the new web archives of this list; it includes all the mails that are in this frozen archive plus all new mails that have been sent to the list since it was migrated to the new archives.

Subject: Re: [OMPI users] How does authentication between nodes work without password? (Newbie alert on)
From: Tena Sakai (tsakai_at_[hidden])
Date: 2011-02-13 17:16:08


Thank you, Ashley, for your comments.

I do have a question.
I was using 'sudo su' to document the problem I am running
into for people who read this mailing list, as well as for
my own record. Why would you say I shouldn't be doing so?

Regards,

Tena

On 2/13/11 1:29 PM, "Ashley Pittman" <ashley_at_[hidden]> wrote:

> On 12 Feb 2011, at 14:06, Ralph Castain wrote:
>
>> Have you searched the email archive and/or web for openmpi and Amazon cloud?
>> Others have previously worked through many of these problems for that
>> environment - might be worth a look to see if someone already solved this, or
>> at least a contact point for someone who is already running in that
>> environment.
>
> I've run Open MPI on Amazon ec2 for over a year and never experienced any
> problems like the original poster describes.
>
>> IIRC, there are some unique problems with running on that platform.
>
>
> None that I'm aware of.
>
> EC2 really is no different from any other environment I've used, either real
> or virtual, a simple download, ./configure, make and make install has always
> resulted in a working OpenMPI assuming a shared install location and home
> directory (for launching applications from).
>
> When I'm using EC2 I tend to re-name machines into something that is easier to
> follow, typically "cloud[0-15].ec2" assuming I am running 16 machines, I
> change the hostname of each host and then write a /etc/hosts file to convert
> from hostname to internal IP address. I them export /home from cloud0.ec2 to
> all the other nodes and configure OpenMPI with --prefix=/home/ashley/install
> so that the code is installed everywhere.
>
> For EC2 Instances I commonly use Fedora but have also used Ubuntu and Solaris,
> all have been fundamentally similar.
>
> My other tip for using EC2 would be to use a persistent "home" folder by
> renting a disk partition and attaching it to the first instance you boot in a
> session. You pay for this by Gb/Month, I was able to use a 5Gb device which I
> mounted at /home in cloud0.ec2 and NFS exported to the other instances, again
> at /home. You'll need to add "ForwardAgent yes" to your personal .ssh/config
> to allow you to hop around inside the virtual cluster without entering a
> password. The persistent devices are called "Volumes" in EC2 speak, there is
> no need to create snapshots unless you want to share your volume with other
> people.
>
> Ashley.
>
> Ps, I would recommend reading up on sudo and su, "sudo su" is not a command
> you should be typing.