Within AWS, consider DynamoDB with the fantastic DynamoDB Lock Client[1]. It’s a “general purpose distributed locking library built on top of DynamoDB. It supports both coarse-grained and fine-grained locking.”
interested to know your approach to long leases lasting more than 60 seconds (if you have this?). do you go for continual renewing (and bailing out if you get too close to the timeout without getting a renewal). or do you go for infinite with your own break logic?
"If you need locks only on a best-effort basis (as an efficiency optimization, not for correctness), I would recommend sticking with the straightforward single-node locking algorithm for Redis (conditional set-if-not-exists to obtain a lock, atomic delete-if-value-matches to release a lock), and documenting very clearly in your code that the locks are only approximate and may occasionally fail."
The redis server reboots. Simple as that. Redis is very very rarely run in a transaction mode that guarantees consistency across reboots (and it's rare enough to doubt the code works even when it is set to the necessary mode). If you're using redis in this mode, it's significantly slower than a proper database, so don't do that either.
