Hot stand by configuration, is possible?
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Hello all, is it possible tu run two installation on different hardwares in a hot standby condiguration?? Thank you!
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Hi ppaniceres,
Yes, it would be possible to use Mango on one machine to assess if Mango is running on another machine, and take over data acquisition and control. It's not a feature built into Mango though, and it would have whatever delay it took to get the data sources running on the second instance of Mango, which may depend on how such a thing would be implemented by the implementer.
What is not currently possible, but people sometimes mean, is for Mango to be running distributed across machines behind a load balancer, but that doesn't seem to be the question.
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Thank phildunlap,
Your answer was exactly what I was wondering, and though a I know I can start a new instance of Mango in a different machine, is it possible to have a slave instance running and being feed with live data from master instance so in case master crashes slave takes datalogging and control and have updated historical data?
Thank you.
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Yes that should be possible too. Simply have mostly the same configuration on two Mango instances on the same network, with one asymmetry being one is publishing its heartbeat to the other (publish system uptime or a random number, whatever) and have a no-update detector on the received point, which has a script to start all the data sources, and then stop them once the first machine is updating that point again. As far as merging after the fact, the easiest way would be to do a NoSQL "Migrate Mango NoSQL Data into Mango" on the second Mango/databases/mangoTSDB and Mango/databases/mah2 after any outage. There may be some issue with the changeover, but that's likely to do with the specifics of your system (i.e. some other host on the network refused the first connection, etc).