When you use the site monitoring feature of CloudMonitor to monitor sites, requests initiated from different detection points may be occasionally closed by the peers in advance (connection reset by peers
). If you find that the destination IP address of the connection is the IP address of a firewall, check whether the security policy of the firewall mistakenly identifies the detection request as an attack or a crawler. If the issue is caused by the security policy settings, configure a whitelist for detection requests.
Solution
Check whether a detection request is mistakenly identified as an attack or crawler by the security policy of the firewall in the log of the firewall. If the detection request is mistakenly blocked by the firewall, you can configure a whitelist for detection requests on the firewall.
You can select an appropriate method to configure a whitelist for detection requests based on the whitelist feature provided by the firewall. The following two methods can be used to configure a whitelist for detection requests on Web Application Firewall (WAF):
Add custom HTTP request headers to the whitelist
After you add custom HTTP request headers to the whitelist on WAF, HTTP requests with the specified headers can bypass the security policy. Then, add the fields of the request headers in the whitelist to the settings of the corresponding detection tasks. This way, the detection requests initiated by CloudMonitor contain the request headers in the whitelist and are no longer blocked by WAF.
Add the source IP address for the specified request to the whitelist
Add the IP address of the detection point from which CloudMonitor initiates the detection request to the whitelist on WAF. You can call the DescribeSiteMonitorISPCityList operation to query the IPv4 and IPv6 addresses of the detection points for all carriers. The query results are updated on an hourly basis.
NoteCloudMonitor occasionally adds or disables some detection points. As a result, the IP addresses may occasionally change. We recommend that you regularly query the IP addresses.