6:14 a.m.
Hi Quanah,
Thanks for your answer. Here are the details asked:
OpenLDAP version 2.4.46.
Mirror configuration on node A:
overlay syncprov
syncprov-checkpoint 100 10
syncprov-sessionlog 100
# Global section
serverID 1
# database section
# syncrepl directive
syncrepl rid=001
provider=ldaps://02.host.com
bindmethod=simple
binddn="cn=root,dc=xxx"
credentials=xxx
searchbase="dc=xxx"
schemachecking=on
type=refreshAndPersist
retry="10 +"
tls_cacert=/usr/local/etc/openldap/cert/cert02.crt
mirrormode on
Mirror configuration on node B:
overlay syncprov
syncprov-checkpoint 100 10
syncprov-sessionlog 100
# Global section
serverID 2
# database section
# syncrepl directive
syncrepl rid=001
provider=ldaps://01.host.com
bindmethod=simple
binddn="cn=root,dc=xxx"
credentials=xxx
searchbase="dc=xxx"
schemachecking=on
type=refreshAndPersist
retry="10 +"
tls_cacert=/usr/local/etc/openldap/cert/cert01.crt
mirrormode on
Thank you very much.
On Tue, Apr 2, 2019 at 7:02 PM Quanah Gibson-Mount <quanah(a)symas.com> wrote:
--On Tuesday, April 02, 2019 4:59 PM -0300 Alex Hebra
<hebraalex(a)gmail.com>
wrote:
>
>
> Hi there,
>
>
> I have a very critical OpenLDAP environment running on mirror mode
> configuration. Is has about 800.000 users.
Hello,
You failed to provide any information on the release of OpenLDAP you are
using and did not provide any information on the replication mechanism in
use. By the sound of it, you are using standard syncrepl, where this sort
of problem is not uncommon, particularly with older versions of OpenLDAP.
I would suggest you start by noting the version of OpenLDAP in use and
providing information on the setup and configuration of the multimaster
nodes.
Regards,
Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
9:09 a.m.
New subject: Help needed: "glued" object.
--On Wednesday, April 03, 2019 11:14 AM -0300 Alex Hebra
<hebraalex(a)gmail.com> wrote:
Thanks for your answer. Here are the details asked:
OpenLDAP version 2.4.46.
syncprov-sessionlog 100
syncprov-sessionlog 100
Hi Alex,
Your sessionlog value is way too small. It needs to be something a little
larger than the entire size of your database (so > 800,000 in your case).
I also see you're using standard syncrepl rather than delta-syncrepl.
Generally, having a "glued" object on a server indicates that at some
point, the server was in a REFRESH mode (either you populated the server
using syncrepl instead of slapcat, or it had some reason to fall back to
REFRESH at a later date).
In the REFRESH mode, the server may get entries "out of order". In this
case, a stub (glue) object is created to "hold" the place for tha entry
until it gets fully replicated. Unfortunately, this doesn't always happen,
and you end up being stuck with the glued object on the server.
You may be able to force replication of the object onto the server where
it's missing by doing a MOD op against the affected entry on the master
where it exists. If one master is "complete" (I.e., no glued objects), you
could also slapcat that master and import the database into the othe
rmaster via slapadd to resolve the problem for now.
Overally, I strongly advise using delta-syncrepl as it largely avoids these
issues (as long as it never has to fall back to standard syncrepl REFRESH
mode).
I would note that there was a fix in OpenLDAP 2.4.47 specific to
delta-syncrepl when ppolicy is in use, so if using delta-sync you likely
want that fix.
--Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
11:19 a.m.
New subject: (was: Help needed: "glued" object.)
On 4/3/19 6:09 PM, Quanah Gibson-Mount wrote:
--On Wednesday, April 03, 2019 11:14 AM -0300 Alex Hebra
<hebraalex(a)gmail.com> wrote:
> syncprov-sessionlog 100
> syncprov-sessionlog 100
Your sessionlog value is way too small. It needs to be something a
little larger than the entire size of your database (so > 800,000 in
your case).
Size of database means number of entries?
Ciao, Michael.
noon
New subject: (was: Help needed: "glued" object.)
--On Wednesday, April 03, 2019 9:19 PM +0200 Michael Ströder
<michael(a)stroeder.com> wrote:
On 4/3/19 6:09 PM, Quanah Gibson-Mount wrote:
> --On Wednesday, April 03, 2019 11:14 AM -0300 Alex Hebra
> <hebraalex(a)gmail.com> wrote:
>> syncprov-sessionlog 100
>> syncprov-sessionlog 100
>
> Your sessionlog value is way too small. It needs to be something a
> little larger than the entire size of your database (so > 800,000 in
> your case).
Size of database means number of entries?
Yes.
--Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
12:54 p.m.
New subject: Help needed: "glued" object.
On Wed, Apr 03, 2019 at 09:09:47 -0700, Quanah Gibson-Mount wrote:
Your sessionlog value is way too small. It needs to be something a
little larger than the entire size of your database (so > 800,000 in
your case).
Hi Quanah
This means https://bugzilla.zimbra.com/show_bug.cgi?id=106848
no longer applies? We were hit by this bug at the time, so we
still have ldap_overlay_syncprov_sessionlog=15000 here.
Geert
--
geert.hendrickx.be :: geert(a)hendrickx.be :: PGP: 0xC4BB9E9F
This e-mail was composed using 100% recycled spam messages!
12:57 p.m.
New subject: Help needed: "glued" object.
--On Wednesday, April 03, 2019 10:54 PM +0200 Geert Hendrickx
<geert(a)hendrickx.be> wrote:
On Wed, Apr 03, 2019 at 09:09:47 -0700, Quanah Gibson-Mount wrote:
> Your sessionlog value is way too small. It needs to be something a
> little larger than the entire size of your database (so > 800,000 in
> your case).
Hi Quanah
This means https://bugzilla.zimbra.com/show_bug.cgi?id=106848
no longer applies? We were hit by this bug at the time, so we
still have ldap_overlay_syncprov_sessionlog=15000 here.
Hi Geert,
I don't know what version of OpenLDAP ships with Zimbra these days. The
underlying issue was fixed in OpenLDAP 2.4.46 (ITS#8486).
Fixed slapo-syncprov session log parsing to not block other operations
(ITS#8486)
Regards,
Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
1:03 p.m.
New subject: Help needed: "glued" object.
On Wed, Apr 03, 2019 at 12:57:51 -0700, Quanah Gibson-Mount wrote:
I don't know what version of OpenLDAP ships with Zimbra these
days.
I think you know it's 2.4.46 :-)
The underlying issue was fixed in OpenLDAP 2.4.46 (ITS#8486).
Thanks for confirmation, we'll revert to a larger sessionlog size.
Cheers!
Geert
--
geert.hendrickx.be :: geert(a)hendrickx.be :: PGP: 0xC4BB9E9F
This e-mail was composed using 100% recycled spam messages!
1:10 p.m.
New subject: Help needed: "glued" object.
--On Wednesday, April 03, 2019 11:03 PM +0200 Geert Hendrickx
<geert(a)hendrickx.be> wrote:
On Wed, Apr 03, 2019 at 12:57:51 -0700, Quanah Gibson-Mount wrote:
> I don't know what version of OpenLDAP ships with Zimbra these days.
I think you know it's 2.4.46 :-)
I honestly haven't tracked it. ;)
Hopefully you don't hit ITS#8843 (For any MMR deployment with > 2 nodes).
Maybe Zimbra has patched this one in?
Hopefully you don't hit ITS#8990. This issue is primarily limited to users
of current versions of python-ldap where they execute a MOD/REPLACE
operation because of the way in which newer versions of python-ldap
re-write the operation into a del+add instead of a replace op. I throw
this one in because I know you have OpenLDAP servers that are not Zimbra
based. ;) Unfortunately this issue existed all the way back to 2011, but
didn't become an issue really until python-ldap changed how it handles
these types of changes.
--Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
11:15 p.m.
New subject: Antw: Re: (was: Help needed: "glued" object.)
>> Quanah Gibson-Mount <quanah(a)symas.com> schrieb am
03.04.2019 um 21:00 in
Nachricht <5C23F01B4C24C3A8ACBCCE7C(a)[192.168.1.39]>:
--On Wednesday, April 03, 2019 9:19 PM +0200 Michael Ströder
<michael(a)stroeder.com> wrote:
> On 4/3/19 6:09 PM, Quanah Gibson-Mount wrote:
>> --On Wednesday, April 03, 2019 11:14 AM -0300 Alex Hebra
>> <hebraalex(a)gmail.com> wrote:
>>> syncprov-sessionlog 100
>>> syncprov-sessionlog 100
>>
>> Your sessionlog value is way too small. It needs to be something a
>> little larger than the entire size of your database (so > 800,000 in
>> your case).
>
> Size of database means number of entries?
Yes.
Hi!
May I ask what the problems are if the value is less? Do changes get lost if
more changes were done than session log can hold while sync can't keep pace? Or
does the server getting more changes simply block until there's spece in the
sessionlog?
Regards,
Ulrich
--Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
9:28 a.m.
New subject: Antw: Re: (was: Help needed: "glued" object.)
--On Thursday, April 04, 2019 9:15 AM +0200 Ulrich Windl
<Ulrich.Windl(a)rz.uni-regensburg.de> wrote:
May I ask what the problems are if the value is less? Do changes get
lost
if more changes were done than session log can hold while sync can't keep
pace? Or does the server getting more changes simply block until there's
spece in the sessionlog?
The server doesn't block anything. The session log is just a list of the
IDs of the entries that changed. When a new one is added to the end of the
list, the oldest one is dropped from the start of the list.
The reason it needs to be so large is to avoid the issues described in
<https://www.openldap.org/its/index.cgi/?findid=8125>
Unfortunately, the session log (currently) does not persist across restarts
of slapd, so it is still possible to hit ITS#8125 with "standard" syncrepl
configurations. Thus one of the reasons I always advise to use
delta-syncrepl.
--Quanah
--
Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>
1705
days inactive
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openldap-technical@openldap.org
9 comments
5 participants
participants (5)
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Alex Hebra -
Geert Hendrickx -
Michael Ströder -
Quanah Gibson-Mount -
Ulrich Windl