Information for: DEVELOPERS   PARTNERS

Pointing DNS records to your public IP addresses

Each Acquia Cloud application has a single public IP address even if the website is an Acquia Cloud Enterprise application using a high-availability hosting cluster of several web servers. The public IP address points to a load balancer, which detects incoming connections to your application and spreads them among the cluster of web servers.

For your application to be available on the Internet, incoming connections must go to the Acquia Cloud load balancer. You can enable availability through your DNS provider by pointing your domain name’s A record entry to the public IP address. In your DNS provider’s web interface, change the A record entry for your domain name to point to the public IP address listed on the Domains page of the Acquia Cloud interface.

For example, if your application’s domain name is www.example.com and your public IP address is 123.123.123.123, you must configure the A record entry for www.example.com to 123.123.123.123.

Your site's IP address

Don’t configure your domain name’s CNAME entry to an acquia-sites.com domain, unless your application uses Resilient Edge Clusters or is hosted on Acquia Cloud Site Factory. Using a CNAME to an acquia-sites.com domain can make your application load inefficiently, and can cause unpredictable results or even downtime if configuration changes or testing occurs on the load balancers. DNS service is not included in Acquia’s uptime guarantee which means if the Acquia DNS provider has an outage, requests to *.prod.acquia-sites.com would fail to resolve, and any domains pointed to the Acquia domain (rather than to a public IP address or an Elastic Load Balancer) would fail.

Note

Acquia doesn’t offer reverse DNS services.

DNS settings with an Elastic Load Balancer

If you have an ELB (Elastic Load Balancer) for your application (which would be the case if you have enabled a legacy SSL certificate for your application), instead of changing the A record entry, change the CNAME entry for your domain name. In your DNS provider’s web interface, change the CNAME entry for your domain name to point to the URL of your Acquia Cloud environment, which will be the URL of your Elastic Load Balancer listed on the Acquia Cloud interface Domains page for the environment.

For example, suppose your application’s domain name is www.example.com and your Production environment’s URL is ab-1234-us-east-1.elb.amazonaws.com. Configure the CNAME entry for www.example.com to ab-1234-us-east-1.elb.amazonaws.com.

The URL of your Acquia Cloud environment may be too long for some DNS providers. Confirm with your DNS provider to ensure they can handle a CNAME for a URL the length of your environment.

Acquia may require verification of your DNS TXT record. If so, the verification will be sent with a hash value.

Important DNS considerations for ELBs

  • Don’t use a DNS A record to point to the underlying IP address of the ELB, since the IP address may change from time to time.
  • You must never use an ELB for several applications or environments. Each environment for each application must have its own ELB.

Using an Elastic IP address

An Acquia Cloud application can use an EIP (Elastic IP Address) to have a static IP address assigned to its server instance. Without an Elastic IP, your instances’ IP addresses are subject to change at any time as the underlying hardware is relaunched or replaced. For most purposes, an EIP doesn’t make a difference for Acquia Cloud applications. You can use EIPs if you must keep the same IP address, for example, so you can add them to a whitelist, integrate them with a Single-Sign-On (SSO) solution, or use a third-party service requiring a static IP address.

An EIP persists when a server is relaunched or rebooted. An EIP will be lost if a server is suspended—for example, after removal due to a downsize.

For Acquia Cloud Enterprise subscribers, using EIPs can reduce your flexibility if you need more server capacity to meet increased application traffic. Although Acquia can efficiently provision new instances for your application in response to demand, Acquia can’t activate the added instances until the new EIPs associated with them can be added to your whitelist or other system.

Changes to IP address

If you have an existing application hosted by Acquia Cloud Enterprise, and you move the application to Acquia Cloud Shield with VPN, your IP address will change (which includes any elastic IP addresses (EIPs)). IP addresses can’t move into or out of a VPC (virtual private cloud).

As a result, when you configure your application in Acquia Cloud Shield with VPN, you must point the DNS records of your application to the new IP address in the VPC. For more information, see Acquia Cloud Shield.