Latest contextcsn is not fetched
Looks like only the first contextcsn is reported, not the last:
root@host3:~# ldapsearch -LLL -x -s base contextCSN
dn: o=Anarchy
contextCSN: 20181206144105.404776Z#000000#000#000000
contextCSN: 20181206225613.485199Z#000000#003#000000
root@host3:~# curl -s localhost:9389/metrics | grep -i csn
# HELP slapd_context_csn ContextCSN timestamp of the base object.
# TYPE slapd_context_csn gauge
slapd_context_csn 2.0181206144105406e+13
root@host3:~#