Re: [SAGE] number of eggs in a basket

[Richard Chycoski <rac@cisco.com>]

In a large organisation, any of these individual services can become 
multiples - for instance we have more than 20 NIS+ domains, all running 
as separate services. Five of the masters are hosted in one DC.

DNS can also become multiple if different servers support different 
domains or subdomains. Computational resources are often divided at the 
machine (or cluster of machine) level for different groups of engineers, 
and each is treated as a separate service. Databases are usually 
separate servers, and we have hundreds of database servers.

Different web services really are different services - sometimes out of 
the necessity of isolating the environment for each web service.

Distinct services should be defined by their distinct environments - 
running multiple instances of a single kind of service (that each 
require their own environment and/or redundancy) is the same as running 
multiple *kinds* of services, except that you should be able to scale 
better if you plan the services properly (e.g., if you have 20 virtual 
web environments each running on a dozen different servers, you may only 
need one or two extra servers for redundancy rather than another dozen).

- Richard


Joseph S D Yao wrote:

>On Fri, Jan 07, 2005 at 10:28:00AM -0800, Richard Chycoski wrote:
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>>If you are virtual web hoster you might have a seperate web 'service' 
>>for each client. ...
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>...
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>The original poster mentioned "services" such as ... Web, DNS, NIS, and
>NFS.  By this definition, the above qualifies as one, or part of one.
>
>However, different Web apps might (MIGHT) qualify as different services.
>As I think you said, it depends on your business.
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