Kentik Synthetics Agents

The following topics provide a high-level overview of Kentik's ksynth family of synthetics agents:

• About Synthetics Agents
• Synthetics Agent Types
• Synthetics Agent Deployments
• ksynth Deployment Considerations

Notes:
- For a general explanation of synthetic monitoring in Kentik, see Synthetics Overview.
- For information on specific modules within the Synthetics section of the Kentik portal, refer to the articles listed under Synthetics in the Contents tab of the KB.
- For assistance with any aspect of the agent setup process, contact Kentik (see Customer Care).

Kentik is able to perform continuous synthetic performance testing from and to network locations both within your infrastructure and elsewhere around the Internet. These tests are enabled by Kentik’s ksynth family of software agents for synthetic monitoring. Kentik offers two distinct types of ksynth agents (see Synthetics Agent Types), each of which may be used in either global or private deployments (see Synthetics Agent Deployments).

The ksynth family of software agents for synthetic testing includes the following agent types:

• App Agent: The app agent runs all of the tests supported by the network agent but can also run an instance of Headless Chromium (Google Chromium running in a headless/server environment), which enables Page Load tests.
• Network Agent: Deprecated as of December 2022.

Kentik's synthetic testing agents are used in the following types of deployments:

• Global Agents: Available to every customer that has activated our synthetic monitoring services, "global agents" are the agents in the Kentik Global Agent Network, a worldwide network of Kentik-maintained ksynth agents. Hosted in data centers and public clouds, these agents enable performance testing to and from key Internet hubs worldwide. Global agents include both network agents and app agents (see Synthetics Agent Types).
  Note: In some portal contexts, the subset of global agents that is deployed in the infrastructure of key cloud service providers (AWS, GCP, Azure, OCI, etc.) is referred to separately as "Public Cloud" agents.
• Private Agents: Every Kentik customer can deploy as many ksynth agent instances as they care to in their own on-prem and/or cloud infrastructure (no additional license required). These private agents are for the exclusive use of the customer who deploys them (not available to other Kentik customers). Private agents may be either network agents or app agents.

The following considerations apply when deploying either the network agent or the app agent version of ksynth:

• ksynth Protocols
• Allowing ksynth
• NTP Configuration
• ksynth Security

Note: For additional deployment considerations that are specific to the network agent, see Network Agent Deployment.

ksynth agents use the following protocols:

• For communication between ksynth and Kentik's SaaS platform (US or EU): TCP 443 (HTTPS).
• For network tests (IPv4 and/or IPv6):
  - Ping: ICMP or TCP (with option to specify target port)
  - Traceroute: UDP or TCP (with option to specific target port)
  - ICMP Echo ping.
• For HTTP(s) or API Tests:
  - HTTP GET/ POST/ PUT/ PATCH sent to TCP port 80/443

Note: Future support is planned for UDP in ping and ICMP in traceroute.

When running one or more ksynth instances on your network, the domains in the table below should be allowed in your firewall rules to ensure that the agents can communicate with Kentik.

The server on which ksynth is installed must be configured as an NTP client to avoid known issues related to clock skew. If the NTP service is correctly configured, the following command should return successfully:

sudo ntpq -p

The ksynth agent generates a unique identity and uses this to authenticate with the Kentik platform. The identity is stored in a local file to be used across restarts and upgrades.