Re: Master replication server reliability

[Tony Earnshaw <tonye@billy.demon.nl>]

tor, 12.08.2004 kl. 02.43 skrev James Courtney:

> I realized that it would be better to have two distinct emails with
> descriptive subjects for my two issues...
> 
> We moved to a replicated system yesterday (1 master and 2 slaves) and
> our mail server components authenticate against the two slaves and our
> updates are done against the master which receives no other traffic. 
> The slave servers have been up since the change but the master server
> has been going down from time to time.  I realized that my CGI was
> very good about unbinding but wasn't calling disconnect on the LDAP
> object when done so I've added this logic.  Could the failure to
> disconnect rather than just unbind cause such problems.  The CGI would
> also exit after running each time so the client endpoint to the LDAP
> server would go away with each run of the CGI.  I'd think that not
> disconnecting explicitly before exiting in the code wouldn't be ideal
> but wouldn't cause the slapd process great difficulty.  Would this
> sort of thing be likely to cause severe slapd problems?
> 
> Also, sometimes slurpd goes down and when it does I end up with a 2 GB
> (exactly) slurpd.replog file containing a great deal of redundant
> update data.  Has anyone else seen this?  Slurpd seems to consume 20%
> + of the CPU on a dual 2.4 Ghz. P4 system with 2 GB RAM while things
> are running normally.  This seems excessive.  Is this symptomatic of
> anything?
> 
> Again my system is Redhat Enterprise 3 ES with OpenLDAP 2.1.25
> (back-bdb), BDB 4.2.52, and OpenSSL 0.9.7d.

Ok, this would be your original posting. You haven't mentioned your
hardware make or configuration. Update your OL version to 2.2.15 -  the
rest should be ok *if* your back-end DB is configured correctly
(DB_CONFIG). RHEL3 has no problem with any of this and can bear
extremely heavy loads, but *only* on good hardware configurations
(well-designed server hardware, *plenty* of RAM, high disk I/O
capability, effective cooling etc) and correctly-configured db backends.
And there is a *world* of difference between the OL version you're using
and OL 2.2.15.

--Tonni

-- 
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mail: tonye@billy.demon.nl
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