The NS1 monitoring solution allows you to create monitoring jobs (i.e., probes) to track the health and performance of a specified device or endpoint. After you create the monitor, you can connect it to a corresponding answer within a DNS record to update the answer metadata automatically.
You can create any of the following monitor types in the NS1 Connect platform:
This article explains the process for setting up a PING (ICMP) monitor and connecting it to answer metadata using the NS1 Filter Chain. Ping monitoring (ICMP/ICMPv6 echo) is a popular technique used to check the availability of network devices. The monitoring system sends an ICMP echo packet to a device and waits for a response. Then, the monitor assesses the connection health based on the specified criteria—such as round trip time (RTT) or percent packet loss.
Verify your firewall settings are configured to allow ICMP/ICMPv6 packets to reach the device under test—otherwise, the "ping" will fail.
In the NS1 Connect platform, navigate to the Monitors page.
Click the + on the right side of the menu to activate the Add Monitor modal.
Select PING from the drop-down list in the upper-left corner.
Under Configuration, complete the following fields:
(Required) Nominal label for the TCP monitor
Toggle the switch to activate or deactivate the monitor. By default, this option is deactivated meaning the monitor is active.
Toggle the switch to activate or deactivate notifications related to this monitor. By default, this option is activated meaning notifications are active.
(Required) Select the locations from which monitoring will be executed.
Select the policy this monitor should use to determine if the monitored endpoint is down. Choose one of the following from the drop-down menu:
Quorum: The host is marked “down” if tests conducted from a majority of the monitoring regions do not pass the “up” conditions.
All: The host is marked “down” if tests conducted from all of the monitoring regions do not pass the “up” conditions.
One: The host is marked “down” if tests conducted from a single monitoring region do not pass the “up” conditions.
(Required) Enter the amount of time in seconds between each monitoring test conducted in each region. The minimum setting is 60 seconds.
Click Add Condition to define the condition(s) the hostname must meet in order to be considered "up." Then choose from the following options:
Round trip time (RTT): The time (in ms) that it takes the ICMP echo packet to go to and return from the tested host.
Percent packet loss: Percentage of ICMP echo packets with no response (timed out).
Next, choose the comparison operator (=, <, >, etc.), and the value to compare. You can add multiple “up” conditions, just note that all conditions must be met in order for a test run to consider the host “up.”
Check this box to automate a second verification test before changing the status of a host. Enabling this option can help prevent false positives.
Under PING Settings, complete the following fields:
Number of packets to send
Enter the number of ICMP echo packets to send. The higher number of packets results in more accurate RTT calculation and packet loss statistics.
IP address or hostname to ping
Enter the IP Address (IPv4 or IPv6) or fully qualified domain name (FQDN) of the device you would like to ping.
Time between packets
Enter a value to indicate the time (in milliseconds) between subsequent echo request packets.
Enter a value to indicate the time (in milliseconds) before a host should be marked as “failed” or “down.” If the RTT is greater than the ping timeout, then that ICMP echo packet is considered as a timeout. This metric influences the percent packet lost “up” condition. For example, if you set the number of packets to four and one of the packets takes longer than the “ping timeout” value indicated, then 25% (1 out of 4) of the packets are considered lost.
Connect over IPv6
If you select this option, the monitor will connect exclusively over IPv6. If checked, verify that you entered either an FQDN or an IPv6 address.
Once complete, click Save Changes. The new PING monitor appears in your list of monitors used.
To complete the setup process, you must connect the monitor to an answer to automatically change the “up” metadata to reflect the status of the monitor. That is, when the tested host meets the "up" conditions, it will change the metadata to up=true. If the tested host does not meet the "up" conditions, the metadata is automatically changed to up=false.
Under DNS > Zones, navigate to the zone and record upon which you want to attach the monitor. Then, click into the record to view associated answers.
Click Create Filter Chain. If your record already contains filters, click Edit Filter Chain.
Select or drag-and-drop the Up filter option (and any other desired filters) to the list of active filters.
Click Save Filter Chain. Now, you can see the Filter Chain configuration to the left of the answer list.
On the left-hand sidebar showing the Filter Chain configuration, click the Up filter to expand that box and reveal filter-specific metadata options.
Click the up: unset metadata label beneath the answer to view the Answer Metadata configuration screen.
Click the icon in the Feed column next to the up/down filter setting to reveal a list of available data feeds—including the monitor you created earlier.
Select the PING monitor you created earlier, and click Ok.
Click Save Record to save your changes.
Now, when the PING monitor detects a failed endpoint, it automatically adjusts the answer metadata to indicate that the endpoint is “down.” As a result, DNS traffic is steered to better-performing endpoints.