I included details in the blog post, the 3.x to 5.x design had the following issues:
- stateful system, with extra data stored in Raft. Always a chance for bugs with stateful systems.
- some corner cases whereby the state rqlite was storing got out of sync with the some other cluster configuration. Finding the root cause of these bugs could have been very time-consuming.
- certain failure cases happened during automatic cluster operations, meaning an operator mightn't notice and be able to deal with them. Now those failures cases -- while still very rare -- happen at query time. The operators know immediately sometime is up, and can deal with the problem there and then, usually by just re-issuing the query.
- stateful system, with extra data stored in Raft. Always a chance for bugs with stateful systems.
- some corner cases whereby the state rqlite was storing got out of sync with the some other cluster configuration. Finding the root cause of these bugs could have been very time-consuming.
- certain failure cases happened during automatic cluster operations, meaning an operator mightn't notice and be able to deal with them. Now those failures cases -- while still very rare -- happen at query time. The operators know immediately sometime is up, and can deal with the problem there and then, usually by just re-issuing the query.