[email protected] wrote: > Full_Name: Emily Backes > Version: 2.4.33+ITS#7427 > OS: > URL: > Submission from: (NULL) (98.155.30.248) > > > We are seeing a condition under heavy conflicting-write load-- i.e. changes to > the same DN from multiple nodes in a syncrepl MMR cluster at the same time-- > where the content of the entry is desynchronized between servers. > > There is a non-reproduced case with incomplete logs where servers traded entry > versions, even with one CSN significantly (by one second) later than the > other. > I'll supply more info if that reappears. > > Additionally, we have a -d logged case of a conflicting write resulting in > different changes applied on different servers while the same CSN gets applied > to both, which seems truly bizarre. > > The expected case is that one server "wins" the conflict and its state is sent > to all of the others, eventually.
Analyzing the logs shows this is an unresolvable conflict in plain syncrepl/MMR. Please note that the Admin Guide already documents the fact that consistency is not guaranteed in this mode. (Section 18.2.2.3.) The solution, as documented, is to use mirrormode. > All of these results are using back-hdb. More details soon, hopefully. -- -- Howard Chu CTO, Symas Corp. http://www.symas.com Director, Highland Sun http://highlandsun.com/hyc/ Chief Architect, OpenLDAP http://www.openldap.org/project/
