Sysdig Monitor uses the concurrent licensing model in determining when to allow an installed agent the ability to connect to our back-end servers and report on host metrics.
This means you can install the Sysdig agent into any number of your instances. However, only the licensed quantity of agents will be allowed to connect and send metrics for recording and reporting.
Agents connect on a "first-come first-served" basis and in the event of an over-subscription (more agents wanting to communicate than are licensed) they will attempt to reconnect on a periodic basis. Once an existing communicating instance goes down and disconnects, the next agent attempting to connect will be allowed in.
To avoid having agents refused connection due to over-subscription, monitor the number of established and allowed connections. To see how many licenses are in use mouse over your login name in the upper right-hand corner of the web interface or see the Settings > Profile page. Use this information to choose purchase additional license capacity in the UI, or to shut down lower priority agents via normal orchestration and system administration means.
- An agent is essentially an "install" of the software. If your system changes external IP addresses, or if you shut down a VM image and bring it back up elsewhere, this will remain the same agent connection. However, identical installs that are simultaneously sending data (usually an accident) will be considered two connections. A MAC address is used to identify a host for licensing purposes.
- When shutting down a host for any reason, the agent's license will not be immediately released. This permits the agent to retain its licensing slot for short outages or a reboot. The time-out interval can take up to 20 minutes and if the connection has not been re-established within the interval, the license will be released for use by the next host waiting to connect.
AWS Services Licensing
The number of items displayed for each AWS service (AWS Services tab) is limited by the number of agent licenses subscribed to. The smallest time window will show approximately the same number of services as agent licenses. However, more items will be listed as you expand the time window since the list will then include historical items previously displayed.
Here are the details on our licensing scheme, the license count:
- Includes Reserved agents plus On-Demand agents (even if not in use).
- Is used to determine how many AWS resources are displayed for each service in each region.
- Is not transferable between different AWS services.
Hierarchy for displaying items per service type:
- EC2 - Pick instances with agents installed, then instances belonging to ECS, then per uptime.
- RDS - Pick by creation time, oldest instances first.
- ELB - Pick by number of balanced instances (larger ELBs 1st), then by creation time, oldest first.
- ElastiCache - Sort by name and display up to 'license count' items.
- SQS - Sort queues by name and pick the first 'license count' queues to fetch. Data is shown only for queues that are reporting metrics.
To increase the limit of items in the AWS Services views, you would need to purchase additional Reserved or OnDemand agent licenses.