Safous ZTNA monitoring schema

Broadly speaking, our monitored infrastructures are: Global Point of Presence (PoP) and App Gateway. Please refer to this article for details: https://support.safous.com/kb/general-architecture.

Method Overview

  • Web test: Is a scenario-based monitoring where agent performs a set of predefined HTTP requests. This can also be used to test the functionality of web application. Collected data which sent back to the monitoring host can be used to set up monitoring alert.
  • Active agent: In contrast with Passive Agent--whereby monitoring host request monitoring data from agent each time host reaches its update interval, Active Agent works the other way around, with the agent actively sending monitoring data to monitoring host every time agent reaches its update interval. Monitoring data can then be used directly to set up alert based on certain threshold without the need of pre-processing.
  • Internal check: In simplest term, this is a self-check. The monitoring host will ask the agent to collect the monitoring data of itself which then sent back to monitoring host--in a similar fashion to Active check, monitoring data is also ready-to-use.
  • HTTP agent: An agent is set up with the sole responsibility of answering request from authorized monitoring host with HTML web page filled with monitoring data as the content. Pre-processing of the return page is needed before monitoring data can be used in the host.
  • External check: The monitoring host will ask an agent to execute a script which supports custom parameters. The agent will simply send the return result of the script back to the monitoring host--in a similar fashion to Active check, monitoring data is also ready-to-use. 

From service side, Global PoPs are monitored using agent-based system. The monitored items includes:

Regional Availability

 
Item Description Interval Threshold Method
Affinity check Monitor PoP availability 1m Response code is not 200 Web test

System Resources

 
Item Description Interval Threshold Method
Load average Monitor current edge load avg (1m, 5m, 15m) 1m > 1.5 CPU load avg Active agent
Memory usage Monitor currently available edge memory in percentage 1m > 90% Active agent
Disk usage Monitor currently used edge disk space in percentage 1m > 90% Active agent
Inodes usage Monitor currently available edge disk inodes 1m < 10 inodes Active agent

Edge Properties

 
Item Description Interval Threshold Method
Agent availability Monitor agent availability 1m Response timeout = 0 Internal
Edge NATS Monitor availability of edge nats function 1m Status code > 0 Active agent
Edge router Monitor availability of edge router function 1m Status code > 0 Active agent
Edge watchtower Monitor availability of edge watchtower function 1m Status code > 0 Active agent

 

Meanwhile from customer side, App Gateway are monitored through agent-less HTTP request. The monitored items includes:

System Resources

 
Item Description Interval Threshold Method
CPU number Total CPU on host 1m - HTTP agent
Free disk Free space left on disk 1m 75% HTTP agent
Free memory Free memory on host 1m - HTTP agent
Host health check Monitor host availability 1m No health check data HTTP agent

App Gateway Properties

 
Item Description Interval Threshold Method
SSL Cert. Validity Check SSL certificate expiration 1d <1d External check
App Gateway Num. Check Number of active App Gateway 1m > #ordered HTTP agent
SSL Cert. Expiration (7d) Check SSL certificate expiration in 7 days 1d < 7d External check
App Gateway Health Check Monitor App Gateway availability 1m Response code is not 200 Web test
Login Health Check Monitor login page availability 1m Response code is not 200 Web test
User Num. Check Number of active users 6h > #ordered HTTP agent
License Expiration Check license status in 90 days 12h < 90d HTTP agent

Since a lot of data are collected from many points around the world, we also set up monitoring proxies in different regions. This to minimize latencies and pre-process collected load with greater flexibility.

Safous Internal Team will receive PoPs and App Gateway's alerts, while customer PIC will only receive alerts regarding their own App Gateway via the registered PIC tenant email.