some general help in setting up a cluster

Robert G. Brown rgb at
Fri Jul 27 16:21:47 PDT 2001

On Thu, 26 Jul 2001, Eric Linenberg wrote:

> I have the ssh daemon running on every machine, and I am running RedHat
> 7.1 so, what am I doing wrong?  Any help is greatly appreciated!

You're working too hard, for one thing.  Create a dsa public key/private
key pair (with ssh-keygen -d) in e.g. ~/.ssh/ and
~/.ssh/id_dsa, put a copy of the public key in ~/.ssh/authorized_keys2.
Make sure that this directory is NFS mounted on all the hosts (or
mirrored some other way).  There are other ways but this should work.

The first time you login to a host you'll probably have to confirm the
hostname/IP number map if it isn't in e.g. /etc/ssh/ssh_known_hosts but
thereafter it should work without any intervention or response.

You may have to monkey with the /etc/ssh/sshd_config files but I recall
that this works for RH's default install so probably not.

Two problems with ssh in RH 7.1 -- for one, they've eliminated the
feature of rsh that a hostname symlink back to the executable acts as
ssh hostname (rats, I've always liked and used that feature).  The other
is more serious.  Due to purported bugs in the linux kernel (there is
some finger pointing and I don't know who's really at fault) one can no
longer background a job in an ssh session and then logout -- the logout
hangs instead of disconnecting the background job from the controlling
tty.  This really sucks.  Hopefully it will get fixed soon WHEREEVER the
problem lies.


Robert G. Brown	             
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at

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