OverviewThe availability monitor can be used to test if a server can be pinged, and will also check to ensure that DNS and reverseDNS capabilities are functioning.
Availablity Monitor Plugin 1.0.0 (compatible with dynaTrace >= 5.5)
Derek Abing: version 1.0.0
Praveen Begur (Dynatrace): version 1.2.0
2013-03-12 Initial Release
2016-01-21 version 1.2.0
2018-02-02 version 1.2.3
DNS Resolved: Returns a 1 if the server DNS name is resolvable and a 0 if the server is not resolvable
Ping Check: Returns a 1 if the server is pingable and a 0 if the server is not pingable
Reverse DNS Resolved: Returns a 1 if the server DNS name is resolvable and a 0 if the server is not resolvable
TCP Check: Returns a 1 if the server is reachable on TCP port 7 and a 0 if the server is not reachable
TCP Lock Time: Returns the time taken to secure a Socket Lock on TCP Port 7
Max TCP Return Time
The max allowed time for the response to the ping in ms
Import the Plugin into the dynaTrace Server. For details how to do this please refer to the dynaTrace documentation.
Changes compared to version 1.0.0
- Removed most of the existing metrics since I found them difficult to interpret and replaced them with metrics named as xxx_violation.
- The plug-in provides two high level metrics for an IT Manager – a) Availability and b) Violation. Availability can either be 0% (something that we are expecting is not working) or 100% (All Green). Violation is num of times Availability is less than 100% (i.e zero %) during a single execution for some technical reason. These metrics help in creating an overall IT manager SLA dashboard showing overall Avail and No of Violations of 100% Avail in a day or week etc.
- Additional metrics named as xxx_violation are provided for specific reasons for overall Availability being less than 100% - Errors like DNS failure, reverse dns failure, ping failure, tcp connect etc.
- Added properties/Boolean flag to make ReverseDNS Test and Ping Test as optional. This was required since earlier plug-in made these tests mandatory with-out giving a choice to the user. Many DC’s disallow Ping and hence Ping test would fail. Reverse DNS Look-up may not work in some DC’s and hence this would fail as well.
- Configure the monitor with target host (as usual) and choose if Ping and Reverse DNS Tests are required or not.
- Create Line or Bucket Chart for Availability (aggregation=average)
- Create Bucket Chart for Violation (aggregation=sum). This tells us how many times in a day was Avail found to be less than 100%.
- Create Bucket Chart for the other Violations like TCP Connect time / DNS / Reverse DNS / Ping etc.
- Note: If more than one type of failure happens – for example Reverse DNS and PING fail, the overall Violation count is still ONE, Avail=100% and individual violations of ReverseDNS and Ping are set to ONE each.
Version 1.2.2 - unreleased
- Fixed availability evaluation, where unreachable hosts remained unreachable until next collector restart
- Added workaround for incorrect result of InetAddress.isReachable() on Windows hosts