Weird DNS round-robin issue

[Dennis Leeuw <D.Leeuw@umcutrecht.nl>]

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Hi all,

I hope I am on the right list for the problem I am experiencing.

We have two subnets
192.168.196.
192.168.222.

Our main LDAP servers run in 192.168.196. and are load-balanced by
round-robin DNS.
The 192.168.196. network is exhausted, so we added a new LDAP slave to
192.168.222. and added the IP address to the round-robin pool.
But it seems that it is only used by other servers in the 192.168.222
network and not by servers in the 192.168.196. network

This setup has now been running for 6 days, with nscd.conf:
	enable-cache		hosts		yes
	positive-time-to-live	hosts		3600
	negative-time-to-live	hosts		20
	suggested-size		hosts		211
	check-files		hosts		yes
	persistent		hosts		yes
	shared			hosts		yes
	max-db-size		hosts		33554432

and nslcd.conf:
uid nslcd
gid ldap
uri ldap://ldap.div.ourdomain.nl/
base dc=div,dc=ourdomain,dc=nl
ssl no
tls_cacertdir /etc/openldap/cacerts

The LDAP server in the 192.168.222 range serves only 33 connections
all from the 192.168.222 range, and the 2 hosts in the 192.168.196
range serve 599 and 706 connections. The last 2 servers do serve the
143.121.222. network also. So might there be some caching issue?

$ getent ahost ldap.div.ourdomain.nl
192.168.196.190 STREAM ldap.div.ourdomain.nl
192.168.196.190 DGRAM
192.168.196.190 RAW
192.168.196.151 STREAM
192.168.196.151 DGRAM
192.168.196.151 RAW
192.168.222.179 STREAM
192.168.222.179 DGRAM
192.168.222.179 RAW

Is this the right list for this question? And if so can someone help
me understand what is going on?

With kind regards,

Dennis Leeuw

- -- 
ICT Medewerker
Divisie Biomedische Genetica
UMC Utrecht
Heidelberglaan 100 STR2.126
3584 CX  Utrecht
The Netherlands
06 27744048
intern: 64048
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