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Alan McKinnon <alan.mckinnon <at> gmail.com> writes: |
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> On 29/05/2015 18:12, Meino.Cramer <at> gmx.de wrote: |
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> > I am makeing definetly something very wrong here...but I the logic |
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> > seems to prevent me to do the rigth ting... |
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*cron* are limited. You need advanced logic constructs to achieve what you |
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want. Bash is most likely your easiest path. |
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> Sounds like a job for anacron. What you want to do is way outside what |
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> the various cron daemons were built to do. |
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> Here's how I would do it: |
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> Run a wrapper script once a day (you do not care when exactly). The |
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> wrapper script creates a state file every time it runs the job the says |
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> when it last ran. Each time the script starts, it checks this file and |
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> figures out itself if it needs to run now or not. |
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All good advice. There are many example scripts about time triggering and |
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counting days to then trigger your desired script. The construct to track |
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elapsed time that I use, is just a simple "accumulator". Once it is full |
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then you trigger your script and zero out the accumulator and start it |
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all over again.... There are many logic constructs that will do what your |
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want. Just hack away! |
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When my mesos work is ready for other, there is a fantastic replacement, |
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call chronos [1] that will fit your needs nicely. Fortunately for embedded |
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guys like yourself, you'll be able to keep your cluster 'live' on milliwatts |
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of power on a small embedded board, then trigger relays or such to boot up |
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other boxes, as the cluster (down to a minimal embedded board) ramps ups to |
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server your needs. I'm making lots of progress; but the more I get working |
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the more I discover that I need other codes and modules..... |
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Maybe you can run the aforementioned anacron on one of your arm boards, |
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for now? |
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Maybe if you wrote your script in Haskell [2], one of the really smart guys |
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would help you debug and get it working (correctly?)..... |
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Have Fun, |
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James |
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[1] http://nerds.airbnb.com/introducing-chronos/ |
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[2] http://www.haskellforall.com/2015/01/use-haskell-for-shell-scripting.html |
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