How to professionally update your server configuration

I've installed several websites on my Ubuntu server and I need now to add an extension and some modules to my php configuration file.

Since I have some e-commerce websites I was wondering if I should put all these websites offline before to proceed with it, and if this is the usual procedure.

Let's say, any guideline for a professional procedure is welcome.

thanks

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You should try serverfault.com for this question –  jmb Sep 21 '10 at 12:12

Whilst this probably would be better suited to Server Fault, I guess it's good practice for webmasters. Here's a webmasters take on your question...

A few points:

1. Give advance notice. It's common courtesy and especially important on an e-commerce site. (Imagine spending hours filling a cart, only to have it all lost when some mug decides to restart apache.)

2. If possible, do a dry run first. Try out your planned changes on a local version of your server. This will save you from being offline for longer than necessary and will mean that any problems can be fixed in a low-stress setting.

3. Make backups! cp php.ini php.ini.bak only takes a few seconds and can save your ass if you botch things. No matter how trivial the modification, make a backup. And don't delete/overwrite it until everything's been thoroughly tested. (I personally keep stable versions indefinitely.)

4. Identify if there's a quiet time across all your sites. If all your e-commerce sites are targeted at users from one country, there'll probably be a quiet period in the early hours of the morning. Updating your server configuration will usually involve some downtime, even if it's just a few seconds, so time your update to annoy as few people as possible.

Hope this helps.

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