Info

We think it is possible to add a shard, create a new database on that shard, and then create one or more unsharded collections on that shard without a change stream noticing that the shard exists. The execution machinery uses an oplog entry indicating a migration to detect that a new shard has been added. But in the scenario above there may be no information in any of the shards' oplogs to indicate that a new shard exists.

Top User Comments

xgen-internal-githook commented on Sun, 22 Dec 2019 06:03:50 +0000: Author: {'name': 'Bernard Gorman', 'email': 'bernard.gorman@mongodb.com', 'username': 'gormanb'} Message: SERVER-42723 Set 'use44SortKeys' on change stream sent to config servers Branch: master https://github.com/mongodb/mongo/commit/8034abccfe1e26e0957fd52906f8e52840b3ae43 xgen-internal-githook commented on Thu, 17 Oct 2019 20:26:31 +0000: Author: {'username': 'gormanb', 'email': 'bernard.gorman@mongodb.com', 'name': 'Bernard Gorman'} Message: SERVER-42723 New shard with new database can be ignored by change streams Branch: master https://github.com/mongodb/mongo/commit/97cc7b5838db4ef13ede3149c44bceca8f5c2977

Steps to Reproduce