41 lines
1.6 KiB
Plaintext
41 lines
1.6 KiB
Plaintext
## ADR #0008: Heartbeat monitors are used to monitor availability
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1. **What did you decide?**
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An Heartbeat monitor shall be used to monitor availability of the engine components of SmartHut.
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2. **What was the context for your decision?**
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Given the existent of three different engine components, the availability monitor strategy shall
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minimize network traffic so at not to overload the network between the three components. The chosen
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strategy shall also be able to effectively give a reasonable indication of availability of each engine
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component of SmartHut, so that the health of the SaaS deployment (and even of the user-controlled
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deployments) may be checked by a dashboard page.
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3. **What is the problem you are trying to solve?**
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Which is the most effective and network-concious technique to monitor availability of engine components of SmartHut?
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4. **Which alternative options did you consider?**
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- Watchdog monitor
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- Heartbeat monitor
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5. **Which one did you choose?**
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- Heartbeat monitor
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6. **What is the main reason for that?**
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An heartbeat monitor implementation requires half the amount of messages between the monitoring component and
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the component to check. With an appropriate clock, a heartbeat monitor can be as effective as a watchdog monitor
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to check availability of engine components.
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Pros:
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- Less network traffic
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- Easier to implement
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Cons:
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- Implementation of services is "active" (i.e. aware of the need to signal availability)
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- Power users with a personal deployment who do not wish to deploy an availability monitor are subjected to additional
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network traffic |