Re: Antw: Re: Shared memory error after reboot

[Quanah Gibson-Mount <quanah@symas.com>]

--On Thursday, January 17, 2019 9:09 AM +0100 Ulrich Windl 
<Ulrich.Windl@rz.uni-regensburg.de> wrote:

> > > > Quanah Gibson-Mount <quanah@symas.com> schrieb am 16.01.2019 um 19:03
> > > > in
> Nachricht <9C84644093A248A4CD6F4653@[192.168.1.39]>:
> > ‑‑On Wednesday, January 16, 2019 5:37 PM +0000 Howard Chu
> > <hyc@symas.com>  wrote:
> >
> > > Must point out ‑ this is not a fatal error, otherwise slapd would not
> > > have continued startup. The backend inits a new shared memory region and
> > > just starts up as normal, there's no reason to take any special action
> > > here.
> >
> > Hm, back when I used back‑hdb + SHM, I have to say I didn't run into
> > this  issue with OpenLDAP unless something had cleared the shared memory
> > region  (i.e., it persisted across restarts of slapd).
> >
> > So while back‑hdb is clearly recovering, there still seems to me to be
> > an  issue here in that short of a server reboot, the SHM segment should
> > remain  unaffected.
>
> AFAIR, those memory files (e.g. __db.001) were needed especially for
> recovering BDB, that is when the database wasn't shut down cleanly. There
> seem to be two problems then:
> 1) Unclean shutdown of the database
> 2) memory files vanishing

I'm talking about SHM shared memory keys.  See the 
slapd-bdb(5)/slapd-hdb(5) man pages for the shm_key option.

--Quanah


--

Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>