[SERVER-52728] Upgrade path from MongoDB 2.4 to 4.2 causes config servers to go down Created: 09/Nov/20  Updated: 29/Oct/23  Resolved: 18/Aug/21

Status: Closed
Project: Core Server
Component/s: None
Affects Version/s: None
Fix Version/s: 4.2.16

Type: Bug Priority: Major - P3
Reporter: Edwin Zhou Assignee: Haley Connelly
Resolution: Fixed Votes: 0
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Issue Links:
Related
Backwards Compatibility: Fully Compatible
Operating System: ALL
Sprint: Execution Team 2021-02-08, Execution Team 2021-02-22, Execution Team 2021-03-08, Execution Team 2021-08-09, Execution Team 2021-08-23
Participants:
Case:

 Description   

Issue

A customer was upgrading from 2.4 to 4.2 and config servers crash because of a conflicting index name in the lockping collection.

2020-11-03T10:57:41.080+0000 F - [rsSync-0] Fatal assertion 40184 IndexOptionsConflict: Failed to initialize config database on config server's first transition to primary :: caused by :: couldn't create lockping ping time index on config db :: caused by :: Index with name: ping_1 already exists with a different name at src/mongo/db/repl/replication_coordinator_external_state_impl.cpp 773

In 2.4.3, a bug caused the "ping_" index to be created (SERVER-9399). Upgrading from 4.0 to 4.2, they crossed the boundary of SERVER-33149 which changed the behavior when an index is created with the same options but of a different name, emitting an error. The secondaries fail to create "ping_1" due to this new behavior. 

Suggested Fix

It would be helpful to soften the check on index "ping_1" so upgrading from 2.4 doesn't come across with that error.



 Comments   
Comment by Githook User [ 17/Aug/21 ]

Author:

{'name': 'Haley Connelly', 'email': 'haley.connelly@mongodb.com', 'username': 'haleyConnelly'}

Message: SERVER-52728 Upgrade path from mongoDB 2.4 to 4.2 requires dropping ping_ index
Branch: v4.2
https://github.com/mongodb/mongo/commit/7853d994db8831e1f91e6c2a59cb01d26f1e6e45

Comment by Connie Chen [ 12/Nov/20 ]

We should error if this ping index is detected on FCV upgrade to 4.2

Generated at Thu Feb 08 05:28:50 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.