Inbound Marketing & Sales Development Inspiration

My website shows HTTP Error 503 Service unavailable -> The real solution.

3 minute read

Administrator   by Administrator August 16, 2012

frustrated with computer graphic

So at this point you have just about pulled all your hair out and are kind of getting a little nervous that the client is going to have problems with their site not being able to handle heavy server loads right? That 503 error keeps coming back though every once in a while and you are at your wits end. Maybe it just happens when you send out a mailer or perhaps you got mentioned on Digg for something pretty cool and your site hits went through the roof?

More often than not we have found the issue is actually related to how your site handles caching

In some cases you might have certain limits on the level of server you have and an upgrade is your main solution, however more often than not we have found the issue is actually related to how your site handles caching. The wonderful folks at W3Edge have produced what has turned out to be quite a popular little plugin for dealing with your cache related problems called W3 Total Cache. We decided to grab their free plugin and give it a test! Note- if you are running an eCom site you will need to use this extra code tweak to prevent cache problems on checkout. It’s also good to have an experienced developer review your code and site briefly as you might spot a few other things that need tweaking before pushing live.

7-7-2015 ow to solve HTTP Error 503 Service unavailable -&gt Blog Post Click to Tweet

Run a test to see how your site handles up to 50 concurrent users

We came across another useful free little load testing tool to help us out called We figured our host could only do so much to help us and so decided to do a little load testing on one of our sites before and after handling the cache. Loadimpact allows you to run a test to see how your site handles up to 50 concurrent users (users all actively using the site at the same time). Here’s what our tests found before we activated the cache plugin (note the site can barely handle maybe 25 concurrent users if cache is not handled … by 50 or more users we start to see 503 errors):

Then … after we installed and configured the plugin … this is what we got (at 50 concurrent users the site pages are still loading in milliseconds as opposed to close to a minute in some cases before). Nice :) Problem solved.

At WebStrategies, Inc, we know how frustrating and often errors can happen when developing or editing websites. Learn more about how we approach web design and development.

Did this fix work for you, or do you have an alternate solution? Let us know in the comments section below.

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