OpenCart Maintenance Checklist
With Christmas 2015 approaching, it's definitely a good time to make sure your OpenCart installation is as stable as possible. So here are a few things that you can check yourself to help avoid any downtime over the festive period.
With each new version, PHP becomes a better and more professional tool, but generally it also becomes stricter at checking for errors in the code. While this is mostly a good thing, it does mean that most sites tend to generate a lot of "Notices" and "Warnings". While your developers should probably look at those at some point, assuming the site all seems to be working, the main concern is that the error logs don't fill up to the point where they break the site - which is surprisingly common. This can break the site either if you run out of disk space or if the log gets to a size that PHP can't open it anymore, which can be quite small on some servers.
Check their size by using an FTP client like Filezilla to check the size of the file at /system/logs/error.log. It shouldn't cause a problem until it gets really big (i.e. hundreds of MB) but if its over 10MB it's probably best to rename it to something like error.log.backup (don't worry it'll be regenerated) and keep an eye on it.
Your website uses space on the web server just like files do on your computer and it's important this never gets too high. Unlike your computer though, warning messages probably won't pop up telling you that disk space is low and the first you'll know about the issue is your site disappears. But if you haven't uploaded any new product images this can't happen right? Wrong! Lots of things could push the disk space over, including the error logs mentioned above, backups running at set times, or session files which are generated as people browse the site. It's also sometimes the case that email is counted towards the limit.
So it's important that you check how much disk space you have available and how much you've used. We'd recommend only using 50% of the available space in case a backup runs. If you leave 50% free, even a full backup should be compressed enough to easily fit in to that space before being removed, assuming your backup service also removes the old backup files of course.
In cPanel you can see your disk space (and bandwidth) on the left column here:
Bandwidth is the amount of data your server has sent and received, usually measured per calendar month and in MB or GB. You never know when you might get a spike in traffic, if a popular site links to one of your products for example, so it's best to have half your bandwidth left at the end of the month. You can check how much you've used with your host, but if they have cPanel (which is by far the best control panel) then you should be able to see the amount you've used on the left. You'll need to bear in mind where you are in the month and how much you've used. If it's the 15th of the month and you've only used 1/4 of your alloance, you're probably be alright (unless you have a big email campaign planned).
If it's looking like it'll be close, then the best thing is probably to upgrade sooner rather than later as most hosts will simply cut your site off when you hit the limit.
Although we wouldn't turn a website off without making every effort possible to contact the owner, most other web hosts have automated software that cuts the site off if an invoice is unpaid for a small amount of time, sometimes even 7 days. You'll only get notified by email (which may of course go to spam) and you'll probably need to pay before they turn it back on if it's been cut off.
If your domain expires, your site will go down and it could be some time before you can get it back again. For SEO reasons it's better to register for multiple years but it's easy to forget when it expires. You can check yours here:
If your SSL Certificate expires, this is also likely to take your site down and/or pop up lots of scary looking error messages. So it's always good to know when it's about to expire. You can check this here:
Server IP Change
Sometimes (although rarely) your host may need to change your IP address. If your domain name is registered somewhere else and does not point to the host's nameservers, you will need to update the IP addresses quickly if this happens. The best thing is to keep an eye out for emails about this from your host and always know where your domain name login details are and how their system works.
Server Upgrade/Planned Downtime
It's best to avoid this in the run-up to Christmas if at all possible, but if that really isn't an option, make sure your developer is available to fix any issues that might arise from an upgrade.
If your site gets hacked then no one will be buying from it. Believe it or not, it happens even to the best sites. How to defend against this? Apart from the usual advice of using strong passwords everywhere, make sure you have automated, recent backups that you can get online very quickly.