I’m the administrator of kbin.life, a general purpose/tech orientated kbin instance.

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Joined 2 years ago
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Cake day: June 29th, 2023

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  • I seriously think we need to ask serious questions if we’re able to shift people point to point further, faster by first going 4 miles towards space for a fraction of the price of moving more people at once on an electrified railway stopping at multiple destinations, picking up and dropping off along the way.

    Something cannot be right. How can they not compete and be profitable? What am I missing?

    Outside of major cities in the UK trains tickets are ludicrously priced.





  • Oh, I forgot about Azerothcore (which is a fork from Trinitycore, and absorbed some changes from certain private server source that has been released in the past).

    Which you choose I think depends on what you want.

    Trinitycore has a more strict development policy of doing things properly and not for example concentrating too much on getting boss fights etc “right”. It’s more of a technical project than “ready to go private server”.

    Whereas (and this is as I understand it, I’ve not done any work for the project directly) Azerothcore is a bit more lax in their requirements. Now, don’t take this to mean they accept bad code. It just means they don’t have the stricter guidelines that trinitycore have.

    I could be wrong though. I’ve been out of the game for a while now.


  • I think so. I would consider perhaps allowing a short time without power before doing that. To handle short cuts and brownouts.

    So perhaps poll once per minute, if no power for more than 5 polls trigger a shutdown. Make sure you can provide power for at least twice as long as the grace period. You could be a bit more flash and measure the battery voltage and if it drops below a certain threshold send a more urgent shutdown on another gpio. But really if the batteries are good for 20mins+ then it should be quite safe to do it on a timer.

    The logic could be a bit more nuanced, to handle multiple short power cuts in succession to shorten the grace period (since the batteries could be drained somewhat). But this is all icing on the cake I would say.



  • My understanding is that the only issues were the write hole on power loss for raid 5/6 and rebuild failures due to un-seen damage to surviving drives.

    Issues with single drive rebuild failures should be largely mitigated by regular drive surface checks and scrubbing if the filesystem supports it. This should ensure that any single drive errors that might have been masked by raid are removed and all drives contain the correct data.

    The write hole itself could be entirely mitigated since the OP is building their own system. What I mean by that is that they could include a “mini UPS” to keep 12v/5v up long enough to shut down gracefully in a power loss scenario (use a GPIO for “power good” signal). Now, back in the day we had raid controllers with battery backup to hold the cache memory contents and flush it to disk on regaining power. But, those became super rare quite some time ago now. Also, hardware raid was always a problem with getting a compatible replacement if the actual controller died.

    Is there another issue with raid 5/6 that I’m not aware of?