Re: [SAGE] number of eggs in a basket

[Skylar Thompson <skylar@cs.earlham.edu>]

On Thu, Jan 06, 2005 at 05:32:37PM -0500, Jan Schaumann wrote:
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> Hi,
> 
> I'd like to get some opinions regarding best practices for mission
> critical systems with multiple services. 
> 
> I have a system that basically is a single point of failure:  if it's
> down, nothing goes.  The services on that machine are WWW, NIS, NFS and
> mail.  Mail is delivered to ~/.mail so mail can be read via NFS and need
> not be fetched.
> 
> I do not like having all my eggs in this one basket, but on the other
> hand distributing the services to several machines seems to complicate
> things and increase the likeliness of one of the services failing.
> 
> So... what are your comments/experiences?  How many eggs do you keep in
> your basket(s)?

Depending on your staffing, I can see two ways to approach this problem:

1. You have a small, or part-time, staff. This means that it can be
advantageous to concentrate all your services in as few machines as
possible, and make those machines as reliable as possible. What you lose in
reliablity you gain in simplicity, making the admins' jobs easier.

2. You have a larger, or full-time, staff. This makes the idea of
one-service-per-machine more realistic, because an admin can concentrate on
one recalcitrant machine while the others keep the workflow moving.

-- 
-- Skylar Thompson (skylar@cs.earlham.edu)
-- http://www.cs.earlham.edu/~skylar/