Checks make use of Sensu representatives to produce observability occasions instantly. Checks guide
you should use inspections observe host sources, solutions, and application wellness along with harvest and analyze metrics. Study Monitor host sources to begin with. Utilize Bonsai, the Sensu asset hub, to discover, install, and share Sensu check dynamic runtime possessions.
Always check commands
Each Sensu check meaning specifies a demand plus the routine of which it ought to be performed. Always check instructions tend to be executable instructions that the Sensu representative executes.
A demand may consist of command range arguments for controlling the behavior for the demand executable. Numerous typical inspections can be obtained as powerful runtime possessions from Bonsai and assistance command line arguments therefore different check meanings may use the executable that is same.
NOTE: Sensu recommends against needing root benefits to execute commands that are check programs. The Sensu individual just isn't allowed to destroy timed-out procedures invoked because of the root individual, that could lead to zombie procedures.
Examine demand execution
All check instructions are executed by Sensu representatives due to the fact sensu individual.
instructions should be executable data which are discoverable regarding the Sensu broker system (as an example, set up in a method $PATH directory).
Examine outcome requirements
Although Sensu representatives try to perform any demand defined for the check, successful check outcome processing needs adherence up to a specification that is simple.
- Outcome information is result to STDOUT or STDERR.
- This output is typically a human-readable message for service checks.
- For metric inspections, this production offers the dimensions collected because of the check.
- Exit standing rule suggests condition.
- 0 shows okay.
- 1 shows WARNING.
- 2 suggests IMPORTANT.
- Exit standing rules except that 0 , 1 , and 2 suggest an UNKNOWN or customized standing
PRO Suggestion: If youвЂ™re acquainted with the Nagios tracking system, you may possibly recognize this requirements вЂ” it will be the one that is same Nagios plugins use. Being outcome, you should use Nagios plugins with Sensu with no customization.
The Sensu agent publishes the checkвЂ™s result for eventual handling by the event processor (the Sensu backend) at every execution of a check command, regardless of success or failure.
Always check arranging
The Sensu backend schedules inspections and publishes check execution demands to organizations with a publish-subscribe design.
Checks have a definite collection of subscriptions: transportation subjects to that the Sensu backend publishes check demands. Sensu organizations come to be customers to these subjects (known as subscriptions) via their specific subscriptions attribute. Subscriptions usually match a certain part or obligation (as an example. A database or webserver).
Subscriptions tend to be effective primitives within the tracking framework you to effectively monitor for specific behaviors or characteristics that correspond to the function provided by a particular system because they allow. For instance, disk ability thresholds could be much much much more essential (or at the least various) for a database host than on a webserver. Alternatively, Central Processing Unit or memory use thresholds could be much much more essential for a caching system than for a file host.
Subscriptions additionally permit you to configure check demands for a complete team or subgroup of methods in place of calling for a normal one-to-one mapping.
To configure subscriptions for the check, make use of the subscriptions attribute to specify a myriad of more than one registration brands. Sensu schedules inspections as soon as per period for every single broker by having a matching membership. A check configured with the system subscription results in three observability events per interval: one check execution per agent per interval for example, if we have three agents configured with the system subscription. For Sensu to perform a check, the check meaning must add a registration that matches the membership with a minimum of one Sensu broker.
Round robin inspections
By standard, Sensu schedules inspections as soon as per period for every single representative through a subscription that is matching one check execution per agent per period. Sensu additionally supports deduplicated check execution when configured using the round_robin check feature. For inspections with round_robin set to true , Sensu executes the check as soon as per period, biking through the offered representatives alphabetically based on representative title.
For instance, for three agents configured using the system registration (representatives A, B, and C), a check configured with all the system registration and round_robin set to real leads to one observability occasion per period, with all the broker generating the big event following a design when it comes to very first six intervals.
When you look at the drawing above, the typical check is performed by representatives A, B, and C every one minute. The round robin check rounds through the agents that are available leading to each broker performing the check every 180 moments.
To make use of check ttl and round_robin together, your check setup also needs to specify a proxy_entity_name . Should you not specify a proxy_entity_name whenever check that is using and round_robin collectively, your check will end doing.
PRO Suggestion: Use round robin to circulate check execution work across numerous agents when making use of checks that are proxy.
It is possible to set up inspections utilizing the period , cron , and submit characteristics.
Sensu requires that checks feature either an interval characteristic (interval scheduling) or even a cron attribute (cron scheduling).
You are able to set up a check is title loans offered in Maine performed at regular periods making use of the period and check that is publish. For instance, to set up a check to perform every one minute, put the interval feature to 60 therefore the submit feature to real .
NOTE: when making an interval check, Sensu determines a short offset to splay the checkвЂ™s very very very first planned request. This can help stabilize the strain of both the backend in addition to representative that can end in a wait before preliminary check execution.