Purism just suffered from a massive dns outage. All their websites were down.
What caused this ? It appears their domain name was unreachable. After looking for a bug in their DNS servers, their was nothing to be found.
The registrar
It came from their registrar. The registrar is the entity from which you rent your domain name (no you don't buy a domain name). They phoned to the hotline but apparently nothing were wrong on their side. They tried to reach their .sm specialist which was unavailable until the morning.
So they waited.
On the morning, the specialist checked everything and found nothing.
We need to go Deeper !
The registry
Deeper their is the registry which sells licences to registrar to rent domain name from their TLD (top level domain, the right part of a domain name).
Bad luck .sm comes from the San Marino in Europe.
So they waited, again, while everything was off.
Purism bypassed their registrar and directly contacted the .sm registry.
The registrar didn't payed the registration fee.
Hahahahaha, i'd love seeing the faces of Purism's technicians when they learned that their registrar was faulty.
So, everything get fixed, everything now works fine.
Conclusion ?
** Choosing a registrar can have direct consequences on the availability of your infrastructure.**
You may have RAID, VM with high availability, a multi-homed network, in multiple datacenters, your domain name and your registrar will ever be your SPOF (single point of failure).
Purism choose to take another domain name in another registrar on another TLD but that's not a perfect solution : if your clients don't try to reach you by your backup domain name… you have no backup.
** Choosing a registry can have direct consequences on the availability of your infrastructure.**
Like you registrar, your registry (it means the TLD you choose) is crucial. Choosing a TLD for its œsthetics can be a future outage.
Even if you host your own DNS servers with fine management, you can still suffer from an outage of your underlying layers.