Overview
Basic settings determine how a GTM instance routes traffic, resolves domain names, and notifies contacts of health check events. The settings include the instance name, CNAME access domain, business domain, Global TTL, alert group, and notification methods.
Procedure
Go to the Alibaba Cloud DNS - Global Traffic Manager page.
On the instance list page, find the target instance and click Settings in the Actions column. The Basic Settings page opens.
On the Basic Settings tab, click Modify.
In the Modify Basic Settings dialog box, edit the Instance Name, CNAME, business domain name, Global TTL, alert group, and notification methods. Click OK to save the changes.
Configuration parameters
Instance name
A user-defined name that identifies the instance and its associated application service.
Business domain name
The domain name used to access your application service. This parameter is optional.
To enable traffic scheduling, go to Public Zone in Alibaba Cloud DNS and add a CNAME record that maps the business domain name to the GTM CNAME access domain.
CNAME access domain
The CNAME domain used for traffic management. Add a CNAME record to point your business domain name to this access domain. To configure a custom CNAME access domain, select a public domain name from your account that is already using Alibaba Cloud DNS as the suffix. The following flowchart illustrates the process:
If your domain name resolution service is not provided by Alibaba Cloud, migrate it to Alibaba Cloud.
If you cannot migrate immediately, use independent subdomain hosting to delegate the subdomain to Alibaba Cloud DNS through NS records, and then generate a custom CNAME access domain.
For example, if the hosted subdomain is
www.example.comand you set the access domain prefix togtm, the custom access domain isgtm.www.example.com.For the resolution source, select either ISP or Chinese mainland regions, but not both.
Based on access policies and health check status, Alibaba Cloud DNS adds resolution records that map the custom CNAME access domain to active IP addresses in the Alibaba Cloud DNS domain name resolution list.
In GTM 3.0, the system no longer generates these DNS records. The interface directly shows the effective policies.
Global TTL
GTM delivers traffic management through domain names. The Global TTL is the duration for which a domain's IP address information is cached in carrier DNS systems. The minimum TTL is 1 minute for the Standard edition and 1 second for the Ultimate edition.
The Global TTL is also limited by the Alibaba Cloud DNS edition of the CNAME access domain. The effective minimum TTL is the larger of the two values:
GTM Ultimate (1-second minimum) + Alibaba Cloud DNS (60-second minimum) = 60 seconds effective minimum.
GTM Standard (60-second minimum) + Alibaba Cloud DNS (1-second minimum) = 60 seconds effective minimum.
To ensure optimal TTL support, associate the CNAME access domain with a Standard or Ultimate Edition instance of Alibaba Cloud DNS.
Alert group
A set of contacts who receive alerts. GTM reads the alert groups that you configured in Alibaba Cloud Monitor. For more information, see Create an alert contact or contact group. You can select up to five alert groups. When a health check detects an issue such as an unavailable IP address or an unavailable address pool, GTM sends a notification to the specified contacts.
Notification methods
To customize alert content and delivery, configure the notification method for each alert event type.
GTM supports the following alert event types:
Unavailable Address
Resumed Address
Unavailable Address Pool Set
Resumed Address Pool Set
Switchover between Primary/Secondary Address Pool Sets
IP Address Change on Monitored Node
For each event type, you can select Email, Chatbot.