We are running the Berkley DB back-end, =B3back-bdb=B2 in the slapd.conf file.
Our server vendor did the upgrade to version 2.4.39 last year in April. In asking them about upgrading to a newer version, as a potential fix, I was told the last version in the RHEL repository that they can upgrade to is 2.4.40. I=B9m not certain that our vendor will support our choice to upgrade to a newer version than what RHEL provides them in the repository, but if it will fix our problem, I=B9ll have to push the envelope on that matter.
Were there any known fragmentation issues with back-bdb in the 2.4.39 version that could also be causing these pauses?
Initially, when we started having problems with the pausing, the server would go offline for about 15-20 minutes then recover itself. The developers had initially set the idletimeout to 8 minutes (480) and we also noted that rsyslogd was constantly logging entries about the slapd service, which stated that the the PID of the slapd service was losing messages to the log due to rate-limiting. Rate limiting was enabled by default for rsyslog so our vendor recommended to turn this off. At the same time, when they did this we scaled back the idletimeout period to 5 minutes (300). This seemed to aggravated the problem. With the original settings, we would encounter this =B3pause=B2 problem maybe once or twice in a 3 month period, and now after these changes were made we=B9re seeing this more frequently, although when it does pause it seems to only be for about 10 minutes, where it was pausing for 15-20 before. We currently have the logging level set to the recommended =B3256=B2, but we=B9re considering lowing the logging level also.
Is it possible we have the idletimeout set too high and it should be lowered? I=B9m wondering if there is some sweet-spot value for this particular setting.
The reason our developers had it set so high was because, in the past they used to run some really long reports. I=B9m pretty sure they do not run these any longer.
I appreciate your feedback.
On 6/6/17, 6:57 PM, "Quanah Gibson-Mount" firstname.lastname@example.org wrote:
--On Tuesday, June 06, 2017 8:39 PM +0000 email@example.com wrote:
Is there a known bug with this version that could be causing this?
Hard to say. It is 3.5 years old and 6 releases behind. You don't state which backend you're using, which may be relevant as well. There were known fragmentation issues with back-mdb in that release, for example, that=20 could cause extensive pauses. Without knowing significantly more about your system configuration, there's only a ton of speculation that can ensue.
You may want to see about using the builds from the LTB project (http://ltb-project.org/wiki/download#openldap), or if you require support for your deployment, Symas (my employer) offers packaged builds and=20 various support options.
Quanah Gibson-Mount Product Architect Symas Corporation Packaged, certified, and supported LDAP solutions powered by OpenLDAP: http://www.symas.com