Today, like the past few days, we have had some downtime. Apparently some script kids are enjoying themselves by targeting our server (and others). Sorry for the inconvenience.
Most of these ‘attacks’ are targeted at the database, but some are more ddos-like and can be mitigated by using a CDN. Some other Lemmy servers are using Cloudflare, so we know that works. Therefore we have chosen Cloudflare as CDN / DDOS protection platform for now. We will look into other options, but we needed something to be implemented asap.
For the other attacks, we are using them to investigate and implement measures like rate limiting etc.
Friend…you have zero idea what you’re talking about. Database existing in multiple locations? What in the hell are you even talking about? Single db instance, multiple app servers, and single LB. You are absolutely not experienced with this type of work, and need to just stop because you’re making an ass out of yourself with these wild ideas that have no basis in practical deployments. Stop embarrassing yourself.
What if your application has to know a state? Say for certain write requests, only one instance is allowed to process those as it needs a cache that it can somewhat consistently rely on?
(Granted, I wouldn’t know why something like Lemmy needs that. But we had that problem at work, and it was a pain to solve while also supporting multiple app instances.)
Distributed lock of any form would work. Memcache, redis, etcd, read access mechanism in an MQ…etc. Only one process would work on whatever it as a time. Simple.