The DNS monitoring feature can detect DNS resolution problems such as DNS hijacking and DNS poisoning at the earliest opportunity. This feature improves the security and stability of DNS resolution.
Overview
The DNS monitoring feature works based on Network Analysis and Monitoring of CloudMonitor. More than 200 monitoring nodes are deployed around the world to help you perform synthetic monitoring on your domain names that are hosted on Alibaba Cloud DNS. You can monitor the performance of the domain names, such as the resolution delay and availability, at different Internet service providers (ISPs) in different regions. The DNS monitoring feature can detect DNS resolution problems such as DNS hijacking and DNS poisoning at the earliest opportunity. This feature improves the security and stability of DNS resolution.
The DNS monitoring feature works based on Network Analysis and Monitoring of CloudMonitor. You must activate Network Analysis and Monitoring before you can use the service. For more information, see Activate Network Analysis and Monitoring.
Benefits
Wide coverage: More than 200 monitoring nodes are deployed around the world. This feature covers major ISPs, provinces, and regions in China.
Good effect: The depth of recursion is reduced on public DNS servers. The speed and success rate of DNS resolution are increased.
Real-time data: This feature allows you to check the status of DNS resolution in real time. This shortens the issue fixing duration, reduces the service downtime, and improves customer experience.
Minimal impact: This feature helps reduce the impact of DNS hijacking and DNS poisoning.
Procedure
Log on to Alibaba Cloud DNS console.
On the Authoritative DNS Resolution page, click More Services tab. Click Use Now button on the DNS Monitoring section.
Click the Upgrade in the Upgrade Notification message to go to the Network Analysis and Monitoring page. Click Activate Now. After you read the billing rules and select terms of service, click Activate Now.
On the DNS Monitoring page, click Add Domain Name and select the domain name and hostname that you want to monitor in the message that appears.
On the DNS Monitoring page, click the Details next to the domain name to obtain monitoring overview.
The DNS Monitoring feature in Alibaba Cloud DNS console does not support a variety of configuration items. To enrich task monitoring and alert rules, see Site monitoring on Cloud Monitor console.
Causes of alerts
For more information, see Error codes and status codes.
Rules
1. Impact of resolution modification on DNS monitoring
DNS monitoring monitors a subdomain based only on the A record or CNAME record. If the record type changes to other types, DNS monitoring stops the monitoring task for the subdomain.
Add a DNS record: If an A record and a CNAME record are configured in different resolution lines for the same host record, DNS monitoring deletes the monitoring task for the subdomain.
Change the DNS record type to A or CNAME: If both an A record and a CNAME record are configured for a host record, DNS monitoring deletes the monitoring task for the subdomain.
Remove a domain name, transfer a domain name across accounts, retrieve a domain name: DNS monitoring automatically deletes the monitoring task for the subdomain.
Delete a DNS record: If the host record has other DNS records, DNS monitoring keeps working. Otherwise, DNS monitoring automatically deletes the monitoring task for the subdomain.
Modify the mapping IP address: The mapping IP address is synchronously updated in DNS monitoring.
2. Limits
You can configure only A records or CNAME records for subdomains if you want to monitor the subdomains by using DNS monitoring.
DNS monitoring supports only the domain names hosted on Alibaba Cloud DNS.
DNS monitoring does not support wildcard domain names.
DNS monitoring does not work if an A record and a CNAME record are configured in different resolution lines for the same host record.
You cannot apply DNS monitoring to the domain names that belong to another Alibaba Cloud account.