Re: Antw: Weird DNS round-robin issue

["Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de>]

>>> Dennis Leeuw <D.Leeuw@umcutrecht.nl> schrieb am 18.02.2014 um 12:24 in
Nachricht <530342DE.2040406@umcutrecht.nl>:
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> Hi Ulrich,
> 
> No I hadn't, didn't even know it existed. But reading up on it it
> seems a server side configuration we do not have.
> 
> Running the getent several times on a host shows nice round-robin
> behaviour, so my guess it is somewhere in the client-side config or
> caching, or...

Do you run nscd?

> 
> Dennis
> 
> On 02/18/2014 12:09 PM, Ulrich Windl wrote:
>> Hi!
>> 
>> Did you read the bind manual pages about "sortlist"?
>> 
>> Ulrich
>> 
>>>>> Dennis Leeuw <D.Leeuw@umcutrecht.nl> schrieb am 18.02.2014 um
>>>>> 10:33 in
>> Nachricht <530328F0.4090903@umcutrecht.nl>: 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
>> 
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