Load Sharing Regarding Large Websites
- by JHarley1
Hello,
I have a question regarding Load Sharing for large websites.
My Understanding:
So if you have a website that has millions of fits a day you will need to have an architecture that can support this sort of pressure. You can either do one or two things:
Invest in a single large server that has huge amounts of processing power, memory and storage (such as Microsoft's TerraServer).
Spread the load of your website across a number of machines.
Let me tackle the second approach, so you have a collection of machines all running Web Server Software and all having access to identical copies of the websites pages. You can either spread the load across these machines using a cyclic pattern in a DNS or you can use a Load Ballancing Switch.
The advantages of this approach is:
- Redundancy - servers can fail and the others would "pick up the slack"
- Incremental - the ability to easily add new machines to this set-up.
My Question's
Is there a Virtual approach to this
issue of load balancing now?
If the website runs from a database -
is there still only a single copy of
the database?
If a user had a session running on
one Server (e.g. they had gone to
www.example.org and had been assigned
to Server 2 - were they had created a
session) if they refreshed the
website (and were allocated Server 3)
would they still have their session?
What are the other disadvantages
associated with Load Balancing?
Many Thanks,
J
