[Date Prev][Date Next]
[Chronological]
[Thread]
[Top]
Re: consistency expectations for 3 node multimaster deltasyncrepl
Zach Hanson Hart wrote:
> Hello list,
>
> TL;DR
>
> With multimaster deltasyncrepl, when the cluster is partitioned (no replication) and conflicting values are added to an entry for a single-valued attribute,
> after the nodes are reconnected and replication commences, is it expected for all nodes to end up with the same value for the attribute, or is it expected that
> they may be inconsistent?
All nodes should end up with the same value.
>
> The long version:
>
> I'm following test063-delta-multimaster in a local test cluster, with 3 master nodes, and I wanted to confirm that I'm not misunderstanding before moving forward.
>
> The test test063-delta-multimaster breaks replication and does conflicting adds of a single-valued attribute (employeeNumber) with different values on the two
> nodes. It then restores replication, gives it a bit to replicate, and then confirms that the "filtered" ldif is the same. My confusion is about this filtering.
>
> In the test, it does
> $LDIFFILTER -s a < $TESTDIR/server$n.out > $TESTDIR/server$n.flt
> and then compares the filtered files.
>
> Does this simply sort the attributes and values, or does it strip values? Essentially, is this testing that the value of the employeeNumber is the same on both
> nodes, or is it simply testing that the employeeNumber is present on both nodes?
You can read the definition of LDIFFILTER in scripts/defines.h. All it does is strip comments and sort attributes.
The employeeNumber will be the same on all nodes.
--
-- Howard Chu
CTO, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc/
Chief Architect, OpenLDAP http://www.openldap.org/project/