[SERVER-14392] Replica set step down behaviour for data not replicated. Created: 30/Jun/14 Updated: 10/Dec/14 Resolved: 01/Jul/14 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | Replication |
| Affects Version/s: | 2.4.6, 2.6.3 |
| Fix Version/s: | None |
| Type: | Question | Priority: | Minor - P4 |
| Reporter: | simon | Assignee: | Unassigned |
| Resolution: | Done | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Participants: |
| Description |
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I have a question about step down. The release notes for mongo 2.0 (we are running 2.4.6) state, ‘To minimize time without a primary, the rs.stepDown() method will now fail if the primary does not see asecondary within 10 seconds of its latest optime. You can force the primary to step down anyway, but by default it will return an error message.’ (http://docs.mongodb.org/manual/release-notes/2.0/) Lets take the following example; There are 2 data nodes, nodeA & nodeB, nodeA is the primary, nodeB is the secondary and is 9 seconds behind. The replica set is told to step down, nodeA becomes secondary, and nodeB elects itself as primary. What I am interested in is, what happens to the 9 seconds worth of data that the primary had when it was in front and told to step down? Is that data 'lost' in a rollback, ie. http://docs.mongodb.org/manual/core/replica-set-rollbacks/ ?? |
| Comments |
| Comment by Thomas Rueckstiess [ 01/Jul/14 ] |
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Hi Simon, The SERVER project is for reporting bugs or feature suggestions for the MongoDB server. For MongoDB-related support discussion please post on the mongodb-users group (http://groups.google.com/group/mongodb-user) or Stack Overflow with the mongodb tag. A question like this involving more discussion would be best posted on the mongodb-users group. Regards, |