Re: Deleted DNs, and the great quest.

[Jorgen Lundman <lundman@lundman.net>]

Quanah Gibson-Mount wrote:
> My only comment would be, if you want reliable replication, use
> delta-syncrepl.

Are you saying syncrepl is known to be broken? Or shoddy in general? I find the 
whole issue that a "top level" of a tree can disappear, but the tree itself 
still works to be troubling. Perhaps BerkeleyDB broken?



I did look at delta-syncrepl, but it never ran very well, and seemed quite over 
complicated for marginal gains. As I understood it, syncrepl always sends entire 
records, whereas delta-syncrepl can update just the attribute of a record. This 
did not sound like it would make any difference. Is my understanding incorrect?


This is what I added to the slapd.conf on master when testing it. Currently, not 
on the production servers.


*** In the middle of slapd.conf

# delta-syncrepl needs full access
access to *
        by dn.base="cn=replicator,dc=company,dc=com" read
        by * break


*** At the end of slapd.conf

overlay accesslog
logdb "cn=deltalog"
logops writes
logsuccess TRUE
logpurge 2+00:00 1+00:00

# define the replica provider for this database
# (last directives in database section)
overlay syncprov
# contextCSN saved to database every 100 updates or ten minutes
syncprov-checkpoint 100 10

# Let the replica DN have limitless searches
limits dn.exact="cn=replicator,dc=company,dc=com" time.soft=unlimited 
time.hard=unlimited size.soft=unlimited size.hard=unlimited


# Accesslog database definitions
database hdb
suffix cn=deltalog
directory /usr/local/var/openldap-data/deltalog
rootdn cn=deltalog
index default eq
index entryCSN,objectClass,reqEnd,reqResult,reqStart
#
dbconfig set_lk_detect DB_LOCK_DEFAULT
dbconfig set_lg_max 52428800
dbconfig set_cachesize 0 536870912 0
dbconfig set_flags db_log_autoremove
dbconfig set_lk_max_objects 200
dbconfig set_lk_max_locks 200
dbconfig set_lk_max_lockers 200

# the access log is also a provider
# syncprov-nopresent inhibits the present phase of synchronization
# syncprov-reloadhint TRUE mandatory for delta sync
overlay syncprov
syncprov-nopresent TRUE
syncprov-reloadhint TRUE



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