Full_Name: Rein Tollevik
Version: CVS head
OS: linux and solaris
Submission from: (NULL) (188.8.131.52)
Submitted by: rein
Syncrepl includes the serverID in the syncCookie in multi-master mode only, but
there are other configuration that would benefit from it as well.
A case I have is where a consumer replicates a glue'ed database, with the
exception of one subordinate backend where the consumer is the master. The
subordinate backend is replicated back to the master of the glue'ed database.
With the current code the master would send the content of the subordinate db
back to its master.
Understood. In fact, having multiple sources of data in a glued tree is really
a form of multi-master. (The separate glued branches cannot cause
inconsistencies with each other, but still their contextCSNs must be managed
A patch that fixes this is at the referenced URL. As I am not sure
consequences if a defaulted serverID=0 value was included in the syncCookie the
patch changes the internal default slap_serverID value to -1 to make it possible
to differentiate between a configured and defaulted serverID=0.
Btw, there are potential problems with using serverID=0, so it would
be best if
that value was reserved for the default unconfigured case. I.e, a default
serverID=0 value could be chosen be slapadd when the two-argument form of
serverID is used in the config, as resolving the URL needs the listener argument
to slapd to succeed.
You mean the three-argument form? The two-argument form only allows a single
serverID to be configured anyway, so there is no ambiguity there. But you're
right, in tool mode when multiple serverIDs are configured, there's no way for
it to choose the right serverID. That's a problem regardless of whether the
default is 0 or -1 though.
For now I think this is a doc issue; we could simply recommend that slapadd
always be performed on the node with ID 0, and you manually change the
serverID config if you need to slapadd on some other node.
-- Howard Chu
CTO, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc/
Chief Architect, OpenLDAP http://www.openldap.org/project/