Forbiden key using client 2.3.0 and server 1.8.1

While preparing migration of our SW from Couchbase server 1.81 to a newer version, I’ve encountered a strange error: “Failed to store the key on the server: Network failure”

After lots of debuging of our code, I’ve finally found that the problem is this key: “47-2014-04-18-balance” (without quotes).

Using plain with just the key changed from “mykey” to “47-2014-04-18-balance” triggers the error.

Combinations of:

  • client 1.0.x and server 1.8.x works
  • client 2.3.x and server 2.x works

What is so special about this key?