There are several causes to why you may not be able to access your cloud server. Some users often mistake the cloud server being down when they cannot access their websites. This would be due to apache being down which may need a restart.
More than often however, a cloud server may appear offline because resources are continuously being maxed out (Out of Memory errors or OOMs), most likely due to memory allocation limits. In this case it may be necessary to upgrade your cloud server by adding additional resources such as RAM and/or CPUs. This can easily be done from within your client area at getsimple.net.
You can open a support ticket to request for a analysis of your cloud server to see what the issue could be.