11 ms·

A mainframe has 100% uptime. Redundancies are baked in by design, hardware maintenance can be performed while the system is live

• _8j50 4y ago
  If that is true then that is enough of a selling point. Cloud providers with 5 9's have one or two outages a year. If you need the uptime for systems that can't have one outage in a decade, is there a competing solution?
  • __d 4y ago
    NonStop? Originally from Tandem, then bought by .. Compaq? And then HP, now HPE. Not a mainframe, but designed and built for 100% uptime. They used to do demos where you could open the cabinet and pull out boards at random, and it'd just keep going. It migrated from custom hardware, to Itanium, to x86-64. It's a custom OS, but has a Unix-like layer on top for ease of porting stuff.
    • jimmux 4y ago
      I used to work on NonStop. I wish it was better known, if only for the impressive uptime stories that did the rounds among the senior gurus. At least one involved firearms.
      • __d 4y ago
        Are you able to share? Sounds ... fun?
• _-david-_ 4y ago
  Can they update firmware without rebooting?
  • rbanffy 4y ago
    You rarely reboot the whole computer. You can take parts of it offline for repairs and the software will route around it. There is a PC inside it running Linux whose job is managing the various subsystems up from powering up the PSU, making sure UPS batteries are charged, that cooling is working even before the CPUs are powered up and microcode is loaded.