When 99.9% reliability is not good enough
Google came out with a blog post yesterday that extolled how much better off you are using Gmail ( available as part of Google Labs ) than running your own mail server. The argument that Google put forth is that average downtime of GMail is much less than if you were using products like Microsoft Exchange or Novel Groupwise. There are some fatal flaws in the Google argument.
- Google averaged out its downtime to get an aggregate 10-15 minutes of downtime per month. But to an end user aggregate downtime doesn't matter. If the email is not available for 15 minutes every month no one would complain. But GMail outages have sometimes lasted hours and in one case Google said it would take a day to restore the service. In fact 99.9% availability means that the service can have more than 8 hours of outage (365 * 24 * 0.1 / 100) That level of outage is simple unacceptable to many businesses and users as email is quite critical to many. Lesson no 1: It is not the average downtime that gets you but the spikes.
- When you run your own email server almost everything is in your control. When GMail is responsible for your email you have no control. When everything is functioning as it should this is great. You don't have to worry about backups and keeping servers up to date etc. In fact this is the USP of Google Apps. But when there is an outage this lack of control especially if you are using the free version is going to frustrate you to no end. In fact if you are an IT administrator you won't have any answers for your boss except that Google is working to restore service. But you don't know how long will they take or if they have lost mails or anything at all. Lesson no 2: With great powers come great responsibilities. But with no responsibilities, you might also end up having no powers at all
Most people have migrated to GMail for two reasons. The best webmail interface among all competitors and to escape from the hassles of running and maintaining an email server. If the former is more important to you than the latter and if you are using Google Apps premier edition (the paid version) then you can still escape an email outage.Using Inbound Gateways and/or Dual Deployment you can route all your email first through your mail server and also access it through GMail. If you configure your MTA to store a copy locally for every email it forwards to Gmail, you have a GMail outage proof setup. But outages of your MTA can still affect your uses as it now a single point of failure. After all, you can't have your cake and eat it too :)
Update: TechCrunch has a post on this.