A 503 Service Unavailable or 508 Insufficient Resource error is caused when a website is being too resource intensive - this means it could be using too much CPU time, too much memory, too much Disk IO or the account may have too many processes running.

As our hosting servers are shared by many customers, each cPanel account has limits on CPU, Memory, Disk and Processes to prevent individual sites from causing performance issues for other customers - this throttles any offending accounts, which can lead to a 503 or 508 error.

A 503 error occurs when CPU, Memory or Disk IO is exceeded. A 508 error occurs when too many processes are running on your account.

Sometimes this is due to lots of traffic on the website - this could be genuine traffic, or traffic from some form of attack, but it can also happen if part of the code is failing to complete and hanging/never finishing, or causing some kind of loop.

This can cause your site to either have too many processes running (if they are hanging/never completing), or it could cause CPU/Memory/Disk to exceed the allowed limits.

Please try clearing your browser cookies/cache (or use a private browsing session) to see if the 503 error stops. If it does, this would indicate that some sort of code error exists. It could be some form of security check, if s Word Press security plugin is being used, it may be this causing it.


However, more often than not, the issue is caused by an issue with part of the code on the website, rather than heavy traffic.

So the first thing to consider is, if this has only recently started happening and hasn't been an issue before, what has changed? For instance, if you've recently installed or updated a new theme or plugin, this may be the cause.

You should temporarily disable all theme or plugins one by one, or revert any updates/changes made to see if the 503 error stops.

You could also restore individual files and your database (if applicable) using JetBackup in cPanel or you can restore the entire account to a point before the changes were made, to see if this solves the issue.

If this doesn't help, looking at the 'Visitors' and 'Bandwidth' area in cPanel -> Metrics can help.

In the bandwidth area, you are looking for a large spike on the graph, if you can see a constant increase compared to previous days/weeks, or if the graph has increased and is still high, this may show that your website is either busy from real or unwanted traffic.

In the visitors area, this shows each request on your website - if there is an attack on your website, you'll quite often see a particular page or file being requested constantly, you may see this coming from the same IP, or many different IPs.

If you see any oddities here, please open a ticket and let us know and we can look to implement a block to prevent the attack, or if you're unsure what the information on these pages mean open a ticket so we can investigate for you.


As a final note, you can monitor your websites resource using in cPanel, real time stats are shown on the right hand side of the main cPanel page for CPU, Memory, Disk and Processes, however these often don't offer enough insight to be useful, unless they are always maxed out.

What is more useful is viewing the historical data in cPanel by going to 'Resource Usage' under 'Metrics'. This will tell you if your site has been limited in the last 24 hours - this is a clear indication that your account is hitting its resource limits.

You can then view exactly what which limit is being hit and see the usage over a longer period i.e. to see if it's started since a change was made, or whether usage has increased gradually etc.

If after following the above you are still stuck, please open a support ticket and we'll do our best to help.

In some situations, your website may simply be more resource intensive than the average website. Previously, our packages all offered the same level of server resource, however our packages now offer different levels of resources so upgrading your package would likely resolve the issue, if you are unable to determine the root cause.

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