(ITS#8268) slapd-ldap quarantine, per configuration retries fail

[nvoutsin@gmai.com]

Full_Name: Nikos Voutsinas
Version: 2.4.42
OS: Solaris/Linux
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (62.38.193.214)


Hi,

In a 4-nodes MMR deployment with a 2-nodes LDAP Proxy Front-ends, we have
repeatedly noticed that whenever the connection recovery method falls into the
quarantine code, it fails.

i.e. when all the back-end ldap servers become unavailable, for some reason,
slapd-ldap fails to follow the retry scheme that is dictated by
olcDbQuarantine.

In our case we set olcDbQuarantine to: 10,30;60,+ and when we got a temporary
network timeout from all back-end ldap server this is what we saw in the slapd
logs.

Oct  7 21:30:58 proxy slapd[330]: conn=632725 op=0 ldap_back_retry: retrying
URI="ldap://back01 ldap://back02"; DN=""
Oct  7 21:30:58 proxy slapd[330]: conn=632725 op=0: ldap_back_quarantine enter.
Oct  7 21:31:08 proxy slapd[330]: conn=632759 op=0: ldap_back_getconn quarantine
retry block #0 try #0.


After that the only method to recover was either to restart the whole process or
reset the value of olcDbQuarantine.

Thanks,
Nikos