Re: (ITS#5661) contextCSN gets corrupted on the stand by mirror

[ali.pouya@free.fr]

Pierangelo mazarati wrote :

> Can you try a fresh reload of the database(s) stripping out the entryCSN
> and letting slapadd generate them, using the -S <SID> switch (along with
> the -w switch), in order to enforce a SID of 001 (or 002, as you like)?


Hi Pierangelo,

I made a new directory with only one contextCSN (SID=002) as you recommended,
and reproduced the contextCSN corruption problem several times.

Example1 :
contextCSN:: 0L0NojA5MDIxMjU5NDkuNzMwMjg1WiMwMDAwMDAjMDAyIzAwMDAwMA==

The four corrupted bytes at the beginning are : D0 BD 02 A2 (hex)

Example2 :
contextCSN:: 4I54oTA5MDIxNTE5MTYuMjYzNDIxWiMwMDAwMDAjMDAyIzAwMDAwMA==

The four corrupted bytes at the beginning are : E0 8E 78 A1 (hex)


I insist on the fact that the problem heppens ONLY if I use TWO syncrepl
directives as recommended in the Admin Guide.
If I use only ONE syncrepl directive, I don't reproduce the problem and the
mirrors get synchronized correctly (whichever mirror side I use for writing).
Also the problem happens on the stand by mirror only when therer are write
operations on the active mirror (> 1000 writes per minute).

I do not understand the interest of using TWO syncrepl directives for
mirrormode.

Thanks for your help
Best Regards
Ali