You may recall a while ago how we covered how to migrate a web server seamlessly with zero downtime. This was great in that specific example as there were no ecommerce websites hosted on that specific web server. Things get a little more complex when with ecommerce websites for several reasons including;
- You won’t want customers placing orders on the website which is still hosted on your old web server as you may not actually pick this up and this would be a very bad experience for the customer and potentially lost revenue
- Your payment gateway technology may actually inform the website on your old server that a payment has been made, but not the website on your new web server due to the way the backbone of the internet works, the DNS.
- Any downtime during an ecommerce website migration between web servers is likely to result in a lot of lost revenue
You simply cannot afford any mistakes when working with an ecommerce website as any mistakes could result in a real mess. All of this is due to the way the Domain Name System, the DNS, works which we’ll go into in a little bit more detail.
In the previous example outlined in the other blog post referenced earlier, we simply updated the name servers and off we went. For ecommerce sites though, this is a problem. Updating the name servers at your registrar (the people you bought your domain name from) can take up to 24-48 hours to fully propagate the whole Domain Name System. Meaning that during this time, some website visitors would see the website that is hosted on your old web server and some customers would see the website that is hosted on your new web server. For many businesses, this is not a problem as the two sites would be identical anyway. For ecommerce websites though, this actively creates problems which then need to be cleaned up later which can be a nightmare. So we need a different approach here.
How to Migrate an Ecommerce Website between Servers with Zero Downtime
A note before we get started, this setup is not a definitive guide to the topic as every single setup is different so please check your own settings before jumping in with changing things unless you are fully sure what you are doing. Making changes with the settings below can result in a lot of problems if you don’t get things right. If you need any support with migrating your ecommerce website, then get in touch and we can help you with this process. . Anyhow, let’s just jump straight into how to do this and we’ll look at the explanations along the way;
- Identify the current DNS Authority: You need to be working with a system which gives you full control over the DNS management, so that you can add A Records to your DNS specifically. The DNS Management is currently sitting with whoever your name servers are pointing at. For example, our name servers, ns1.contradodigital.com and ns2.contradodigital.com mean that our DNS is being managed by contradodigital.com. If your name servers are set to your registrar then this is who the authority is for your DNS settings.
- Migrate your DNS Settings: Generally speaking, when you are migrating your ecommerce website you are also wanting to migrate your DNS management from your old supplier to your new supplier. Assuming this, then you’ll need to migrate your DNS settings first. Firstly you need to look at all of your current DNS settings that are in place and migrate all of these settings, except the name server settings, over to your new DNS Authority.
- Keep the A Record in the DNS Settings at your new DNS Authority the same for now: As part of the DNS settings migration you just did, you will have copied over an A Record which is specifically used to tell the Domain Name System what the IP address of the server is when someone types in http://example.com or http://www.example.com into their browser. For now, keep this record pointing at your old web server so that everything continues to work as normal.
- Sit back and wait 24 hours: As the Domain Name System can take a while to update all the records everywhere, just go and do something else for a while until you are confident that the systems have updated. Most systems are much faster than this, and we can actually customer the Time To Live (TTL) with our DNS Management which means we can specifically set the amount of time other computers should store certain information they have about the DNS settings before requesting the information again from the authoritative source. This comes in extremely useful later on which is why we can migrate an ecommerce website with zero downtime (almost).
- Update your Name Servers: The name servers at your registrar will currently be pointing to your old DNS Authority, likely the same company who managed your old web server. You need to update your name servers to point to the correct location for the company who is managing your DNS from now. For example, when companies are migrating their web hosting to us, this means that they would update their name servers to ns3.contradodigital.com and ns4.contradodigital.com.
- Sit back and wait 24 hours: As before, we now need to wait a while for the Domain Name System to update all of the data so that the new authority for the DNS management is your new company. During this time, as people visit http://www.example.com, some people will see the old name server settings, which means they will view the website on your old server, and some people will see the new name server settings, which means they will also view the website on your old server as we kept the A Record the same so that the website continues to work.
- Migrate the Website: This is very specific to each website, technology and other server settings that need to be migrated so we won’t touch on the topic a great deal here. Suffice to say that whatever technologies you are using, you need to copy across the files, databases, plugins, extensions, well basically everything. If you miss anything during this point you will be picking up the pieces afterwards. When migrating your database specifically, you may find that you need to do a bit of intermediate work to update the table names potentially based on how the old and new servers automatically generate the table names for any website technologies you are using so bear this in mind.
- Add a Holding Page on the Website: This is extremely important to do this during the migration to avoid any activities happening on the website on the old server as we would need to comb through the differences and manually migrate anything that happened during the time from migrating the website to updating the A Records later on. Depending on your technical setup, websites purpose and other factors, you may choose to do this before Step 7 which would mean the website would be offline for a short period of time but would mean that you don’t need to implement Step 9 below.
- Migrate the Database Again: For ecommerce websites, the majority of the activities are database driven from users, such as purchasing a product or commenting on a blog post. There is often very little files that are uploaded to the website which means that you should be OK to just migrate the database one last time. Your website may be different though, so if in doubt, get in touch and we can guide you through the process. It is essential that your holding page throws a 503 Error in the header or your Google website rankings will fall off a cliff, meaning your website traffic and revenue will follow and could take a few weeks to recover. Google’s guidelines on dealing with planned maintenance is useful to read over.
- Update the A Records to Point to the new Web Server: Now you have migrated the database again, the website on your new web server is ready to go live. So pop back into your DNS settings and update the A Record to point to the IP address of your new web server instead of your old web server. As mentioned earlier, you are better off if you can manage the Time To Live (TTL) settings directly so that you can speed up the time it takes for the new settings to spread throughout the Domain Name System.
- Deactivate the Holding Page: Your website on the new web server is ready to go, so let your customers come flooding back in!
The entire process above means that your website should be offline for no longer than 5-10 minutes (virtually Zero downtime!). If you get anything wrong within this process of you don’t have the ability to manage certain settings then this clearly may take longer, which is why we always recommend you use a reputable web hosting company and that you are working with the right digital agency who has the skills, knowledge and expertise to manage this effectively for you.
For Windows users, several of the steps above require changes to your hosts file so that you are sure you are looking at the right web server when making changes. Make sure you double check your hosts file settings throughout the entire process to make sure you are doing what you think you are doing on the right server as it could cause you problems if you do the wrong thing. Particularly if it is database related and you accidentally overwrite your database with a blank database. That would not be good.
Considerations during the Migration
Any business has many moving parts, all of which touch on the website in one way or another. For larger businesses you need to really plan the timelines involved with this process and communicate this with everyone in your organisation. The last thing you want to see is customers calling you about a problem and your staff not being able to access your website for further information or have no idea about what is going on;
- SEO: From an SEO point, you need to make sure your website is throwing a 503 Error in the header to avoid you losing your website rankings, traffic and sales during the migration. Getting this wrong can result in a situation taking a good few weeks to resolve itself. Google’s guidelines on dealing with planned downtime are useful to read over.
- PPC: Are you running any pay per click advertising campaigns currently that need to be paused during the migration? If Google AdWords picks up that they are seeing 503 Error messages on your website, they will start to flag problems within your Google AdWords account. So it’s always best to pause these if your planned downtime may not quite go according to plan. Alternatively for high volume websites you may decide to continue running AdWords campaigns to maximise revenue during the process and simply mop up and messages that have been flagged within your AdWords account afterwards.
- Email marketing campaigns: Communicating with your entire business means that you aren’t going to be sending out any email marketing campaigns during your planned website migration. Sending out an email marketing campaign resulting in hundreds of thousands of extra visitors trying to access the website only to find it is not available for those few minutes can damage your branding.
- Social media activities: As above, it’s best not to plan any significant social media campaign during this time which encourages customers to visit your website for the same reasons as outlined earlier.
- Offline activities: Are there any offline activities within your business that could be impacted by a short period of time with the website migration?
- Server settings: Are there any other server settings that you need to be aware of during the migration such as SSL certificates, redirects that have been implemented in a server control panel, email accounts or mail forwarders that have been set up on the server instead of on Microsoft Exchange? Double & triple check everything because in our experience, it is that one setting that everyone forgot about or never knew was implemented on the old server which causes the biggest problems.
Migrating an ecommerce website with (virtually) zero downtime requires a lot of planning, the right systems, technology and people in place to get things right. If you are in any doubt about migrating your ecommerce website then get in touch and we can guide you through the process.
Latest posts by Michael Cropper (see all)
- How to Use the Vi Text Editor on Linux Guide for Humans - May 18, 2020
- How to Install Nano Editor on CentOS 7 - May 18, 2020
- Handy Database Design for Records to Track Created Date Time and Updated Date Time - April 2, 2020