On Wed, Jul 23, 2025 at 11:22 AM Owen DeLong via Outages-discussion <outages-discussion@outages.org> wrote:
Most datacenter contracts prohibit batteries in your cabinets. For good reason, relating to fire codes and firefighters knowing where to expect such hazards. The far better solution is yo have something external that can notice when a datacenter goes away or services stop responding.
There must be some amount of battery power you can have, as just about every server holds a lithium button cell to retain system clock plus something like a 1000 mAh Lithium Ion pack to protect the RAID controller cache. rechargeable RAID controller cache batteries found inside the chassis of just about every server, and on storage filer heads. Which is more battery capacity than you need to keep a small dedicated SBC and cellphone live for a few minutes to send an alert. That's something which should not need a UPS with a whole extra shelf full of batteries. I'd suggest the best solution is have both internal and external monitoring. It is good to be able to know immediately if the externally-detected outage is due to power or due to network, and an only external monitor cannot say which one of those.
Owen -J