Having done some more research, it appears that Active Directory also has some settings that could result in disconnected connections. I experimented with idle-timeout set to 30 seconds for the LDAP databases, but this seemed to exacerbate the frequency of the errors. The behaviour exhibits as ‘dead’ connections, and LDAP does not appear to attempt to re-establish these connections. Using the CentOS distro of OpenLDAP 2.4.23

 

Here are the slapd.conf settings:

 

database                ldap

readonly                on

suffix                  "dc=xyz,dc=local"

#noundeffilter           yes

#use-temporary-conn      yes

uri                     "ldap://IP1/ ldap://IP2/ ldap://3/ ldap://IPn/"

 

 

database                ldap

readonly                on

suffix                  "dc=abc,dc=adroot,dc=abc,dc=bc,dc=ca"

#noundeffilter           yes

#use-temporary-conn      yes

uri                     "ldap://IP11/ ldap://IP12/ ldap://13/ ldap://IP1n/"

 

 

I have some rewrite rules for bindDN, searchEntryDN, searchAttrDN, matchedDN, but I don’t believe these settings are relevant to the issue at hand.

 

Essentially I want the connections to be re-established without generating errors.

 

Thanks

_____________________________________________
From: Bryce Powell
Sent: December 10, 2012 01:32 PM
To: openldap-technical@openldap.org
Subject: LDAP database timeout settings

 

 

Hi,

 

I have configured two LDAP backend databases, each pointing to a difference Active Directory domain (multiple domain controllers specified per domain). After a period of time after slapd starts, the ldap log file shows multiple entries like this for the various connections (conns=nnnn):

 

Dec 10 13:18:03 vmxxxldap01 slapd[7826]: conn=1004 op=27 SEARCH RESULT tag=101 err=1 nentries=0 text=000004DC: LdapErr: DSID-0C0906E8, comment: In order to perform this operation a successful bind must be completed on the connection., data 0, v1db1

 

Without going into too much detail regarding the configuration, I’m wondering if I need to specify LDAP database configuration settings for:

idle-timeout

network-timeout

 

man slapd-ldap:

 

       idle-timeout <time>

              This directive causes a cached connection to be dropped an recreated after it has been idle for the specified time.

 

       network-timeout <time>

              Sets the network timeout value after which poll(2)/select(2) following a connect(2) returns in case of no activity.  The value is in seconds, and it can be specified as for idle-timeout.

 

 

I don’t understand the explanation for network-timeout though, and am hoping someone can kindly explain it in more detail, and suggest a scenario for its appropriate usage.

 

Also, when is it appropriate to use the ldap.conf NETWORK_TIMEOUT setting?

 

man ldap.conf:

 

       NETWORK_TIMEOUT <integer>

              Specifies the timeout (in seconds) after which the poll(2)/select(2) following a connect(2) returns in case of no activity.

 

 

 

 

Could someone please suggest the best approach for my use case?  Of course, I might also be completely off the mark here …

 

Thanks

Bryce Powell