Web application advice - how to create a 'down for maintenance' page

[rogoff]

I'm about to build a web application that could have thousands of paying customers. We will need to take the application down now and then for upgrades and maintenance? What is the best practice method of doing this? We'll probably be using PHP, Apache, MySQL.

Anyone got any good suggestions?

[edited by: phranque at 12:48 pm (utc) on Aug. 14, 2008]
[edit reason] No urls, please. See TOS [webmasterworld.com] [/edit]

[rogoff]

I have seen 2 methods of doing this so far:
1) using mod_rewrite to redirect all requests to a maintenance page
2) using a configuration file which contains a maintenance 'yes'/'no' flag which is checked by every page of the site. This method also had an ability to only allow certain users to access the app while it was in maintenance mode.

So, anyone got any other good suggestions?

[edited by: phranque at 9:06 pm (utc) on Aug. 14, 2008]

[janharders]

absolutely 2) ... you'll still want testing and crew members to be able to access the site without the public jumping around. but in general, you'll not want to take it down for maintainance any time. I mean, testing should be done on a seperated machine, and a maintainance-downtime should only occur if you're updating the software. to the user, any downtime is bad ... even if you're thinking "hey, let's just take it down in the middle of the night" ... those, that are trying to accomplish something while your site is down will be disappointed.

[rogoff]

Thanks for the info. Yes, I'm hoping that it will mostly be used for upgrading the app but I suppose there could be times we need to take it down for an emergency fix.

Yeah, I think the config file is going to be the best option. Especially if we want to be able to test the production version after an upgrade.