[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: how to configure multi-master



On Monday 21 July 2008 14:48:23 Liutauras Adomaitis wrote:
> On Mon, Jul 21, 2008 at 12:49 PM, Buchan Milne <bgmilne@staff.telkomsa.net>
>
> wrote:
> > On Sunday 20 July 2008 23:34:03 Liutauras Adomaitis wrote:

[...]

> > > It shows, that it is adding MirrorMode TRUE. So why?
> >
> > The configuration directive may have been overloaded when multi-master
> > was added (after mirrormode). AFAIK it allows the database in question to
> > both have a syncrepl directive, yet take updates from a DN besides the
> > updatedn (see the description on the slapd.conf man page).
>
> are you saying, that in multimaster configuration I have to have updatedn
> directive to be able to do writes?

No. Without mirrormode or multi-master, a slave would only accept updates from 
the updatedn. In multi-master, the master is also a slave, so it needs to 
accept updates from any DN, while being configured as a slave (having 
replication configuration).

> I didnot find anything about that in documentation
> http://www.openldap.org/doc/admin24/replication.html. On the other hand man
> page says:
> updatedn <dn>
>               This option is only applicable in a slave database.
>
> > > man page of slapd.conf states:
> > > "mirrormode on | off - This  option  puts  a replica database into
> >
> > "mirror"
> >
> > > mode...."
> > > Adding this to my conf file lets me do writes to masters, but I don't
> >
> > want
> >
> > > MirrorMode, I want MultiMaster.
> >
> > See the rest of the paragraph, which continues to say:
> >
> > "Update operations  will  be  accepted  from  any  user,  not  just  the
> > updatedn."
> >
> > Regards,
> > Buchan
>
> In thread "explain diff between multimaster and mirror mode" I found out,
> that mirrormode is kind of high availability implementation for openldap.
> In my case I want to have multimaster replication, which could allow me to
> do writes to different master servers at a time.

You may want to think very carefully about why you want this, and not 
mirrormode, or a single master.

> It contradicts mirrormode,
> which says, that writes should be directed to one master and switched only
> on failure of first master.

But the prerequisites (replication, as well as allowing writes from an 
identity that is not updatedn) remain the same for both.

> I would like to stress my question again: how to do writes in multimaster
> configuration? Simply following documentation didn't let me do writes to
> any master.

I succeeded by reading the documentation ...

Are you sure it is not some other aspect of your configuration? Have you 
posted details? Have you posted the error message?

Regards,
Buchan