• P03 Locke@lemmy.dbzer0.com
    link
    fedilink
    English
    arrow-up
    3
    ·
    edit-2
    4 hours ago

    Five nines means that you need people at their desks in shifts ready to start fixing something the moment there’s a problem

    No, it means you don’t have outages. Ever.

    Five-nines is something like 7 minutes of downtime throughout the entire year. At best, you might have automated failover systems that require tiny outages. No human involvement, though, unless you’re deal with some major breakage that would have killed the five-nines commitment that year, anyway.

    It’s takes a human something like 5-10 minutes just to get out of bed and figure out the situation, anyway.

    • merc@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      4
      ·
      3 hours ago

      No, it means you don’t have outages. Ever.

      No, that’s infinite nines, which isn’t possible.

      Five-nines is something like 7 minutes of downtime throughout the entire year. At best, you might have automated failover systems that require tiny outages. No human involvement, though, unless you’re deal with some major breakage that would have killed the five-nines commitment that year, anyway.

      Yes, you have automated failover systems. But, if something happens which causes those systems to fail over, you need to immediately investigate what happened and why. Even at four nines you have automatic failover, redundant system, hot spares, etc. But, you accept that sometimes not everything will work as planned and you’ll need to fix something. Five nines is just that and more.

      It’s takes a human something like 5-10 minutes just to get out of bed and figure out the situation, anyway.

      Right, which is why I said that four nines is your realistic maximum if you’re going to have people on call who aren’t actually at their desks. To get better than four nines you need to have around the clock coverage with people at their desks so when a system breaks you have eyes on it in something like 30s.

      • P03 Locke@lemmy.dbzer0.com
        link
        fedilink
        English
        arrow-up
        1
        ·
        3 hours ago

        No, that’s infinite nines, which isn’t possible.

        It’s not impossible. Large reliable websites do it all the time. It’s call 100% uptime.

        Sure, it’s measured per year, and sometimes they have some outage that breaks the record. But, it is possible to have 100% uptime throughout the year.

        • merc@sh.itjust.works
          link
          fedilink
          English
          arrow-up
          3
          ·
          3 hours ago

          It’s not impossible. Large reliable websites do it all the time. It’s call 100% uptime.

          No, no website does it. There is no such thing as 100% uptime. If it happens, great, but I can guarantee you that no website even aims for 5 nines of uptime.

          Google is the benchmark for website availability and in 2022 they had an outage that lasted an hour, meaning they didn’t meet 4 nines for the year.

          Sure, it’s measured per year, and sometimes they have some outage that breaks the record. But, it is possible to have 100% uptime throughout the year.

          If you miss your SLO target for the year, then you missed your SLO target. If you’re down for 60 minutes but fine for the other 11 months, 29 days and 23 hours, you still missed your yearly SLO.