MySQL 5.5 Crashes After Downgrade from 5.6 Version

(Doc ID 2344262.1)

Last updated on DECEMBER 30, 2017

Applies to:

MySQL Server - Version 5.5 and later
Information in this document applies to any platform.


On : 5.5 version, Server Crash

When attempting to authenticate via plugin,
the following error occurs.

Signal 11

The issue can be reproduced at will with the following steps:
1. Have a working install of 5.5
2. Upgrade to 5.6
3. Downgrade again to 5.5

The issue has the following business impact:
Due to this issue, users cannot trust the authentication and privileges being used by MySQL.


Downgrade from 5.6 version.


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