[Bioclusters] About RSH/SSH in Cluster

Yun He jarod at spg.biosci.tsinghua.edu.cn
Thu Mar 3 07:28:35 EST 2005

RSH is occasionally broken when many small files transferring simultaneously. 
Since RSH usually runs as an internal service in INET server or XINET server 
rather than a stand alone service, it increases the cost of response to the 
server especially when there are thousands of files transferring 
simultaneously, each transfer action will tell the INET server to start a new 
process to do it, so the INET server sometimes will be dead. I had  
encountered this situation once, at that time I had to restart the INET 

On Thursday 03 March 2005 09:34, you wrote:
> >>If I use ssh with key authorization,  could I need to use an
> >> empty-password
> private key ?
> Yes, we do it all the time. And to make the "small" overhead smaller, you
> can consider using a 512-bit encryption, which is the minimum.
> >>Which is better? Which is more efficient ?
> Theoretically, rsh would give better performance since it does not encrypt
> the communication path as everything is sent in plain-text. However, rsh is
> less stable than ssh (at least from my experience, thus far). Passwordless
> login will work for a while and then out of the blue, it'll just stop
> working. Happen to one of our cluster for a VR system not long ago and it
> had to happen during the training when the big boss of the client was
> around. We had to use some stupid "network problem (microsoft virus)"
> excuse to buy time to solve the problem. In the end, we just replace the
> rsh command with a symbolic link to the ssh command (had to use rsh cause
> the VR software insists on using it).
> Hope this helps!
> "Leadership & Life-long Learning"
> Alan Ng
> Software Development Engineer
> Linux Certified Professional
> Open Source Systems Sdn Bhd
> www.aldrich.com.my  Tel: 6 03-8656 0139   Fax: 6 03-8656 0132
> -------------------------------------------
> "Carpe Diem: Seize the Day!!"
> Yun He wrote:
> >Many applications in cluster need password-free environment, such as
> > OpenPBS or Torque, usually, there are two ways to let us login into
> > different nodes of cluster without giving a password, one is to use rsh
> > with .rhost file in each home directory, another is to use ssh with RSA
> > key authorization. Which is better? Which is more efficient ?
> >If I use ssh with key authorization,  could I need to use an
> > empty-password private key ?
> >
> >Thanks
> >
> >                  Jarod
> >_______________________________________________
> >Bioclusters maillist  -  Bioclusters at bioinformatics.org
> >https://bioinformatics.org/mailman/listinfo/bioclusters

More information about the Bioclusters mailing list