MyLinuxTips

Are you running multiple stand alone installations of WordPress sites for either yourself or clients? Sick of having to log into each site every time there is a core update or plugin/theme update to apply? Then multisite may be your answer. WordPress 3 has made it possible to host multiple domains within one installation of wordpress. While, in theory, this sounds like a plus, but there are many pros & cons of it and you should seriously consider them before jumping in to hosting multiple domains on your single WordPress installation.

Advantages (Pros) of using the WordPress 3 Multi-site Feature:

You should use the multi-domain application under the following circumstances:

1. You need the minimal time savings of installation and limiting the number of MySQL databases you use.
2. You will always want the same theme and plugins for all of your websites.
3. You never want to switch web hosts.
4. You will never sell any of the websites you build.
5. It is not critical to your business if all of your websites go down at the same time.
6. You do not plan on ever making your sites large enough to become a problem with backing them all up at once.
7. Have a Multi Blog Platform – Users can register easily and have a blog on a  domain of your own, just like WordPress does.
8. One super admin user logon for all your sites.

Disadvantages (Cons) of WordPress 3 Multi-site Feature:

1. Lack of versatility. Unless you want to use the same theme for all of your websites, you will need to purchase a theme such as the Builder theme that will allow you to have different layouts for your sites. You must also run all of the same plugins on all of your sites which may not be to your advantage.
2. Lack of security. For whatever reasons, hackers love to find back doors into WordPress. If all of your websites are hosted within one application, it makes them all equally vulnerable.
3. Domino effect. If there is a technical problem within one site, all of your sites could be down at the same time. This effectively puts you out of business until the glitch is worked out. Having your sites on separate installations would allow you to have sites that are still operational if there is a problem with one of them.
4. Database backups. Creating backups for several smaller databases is easier than doing one huge backup file.
5. Changing web hosts. If you ever want to switch web hosts, having separate installations makes the process easier. You may have an instance where one of the domains has become very popular and is using up a great deal of your hosting resources. In this case you would want to move that domain to it’s own account. If it is all wrapped up with all of your other domains within one WordPress installation it would be very difficult to separate it after the fact.
6. Selling your site. You may decide sometime down the road that you would like to sell one of your websites. This would be almost impossible if it were sharing a database with other domain names.
7. Not all plugins support multisite installation.

So consider your requirement case before directly switching to multisite feature of wordpress.