RE: achieve server redundancy

[<Kent_Wu@trendmicro.com>]

Round robin sounds good however it still hasn't solved my real issue.
What I want to achieve is failure-recovery, through Round Robin I can achieve
a bit load balance however when one server is down, the client who happens to be RR'ed to query that server 
is going to get an error response still. It seems the load balancing switch might be a good choice since it would probably try to detect the status of those servers.

	I know windows domain controller works this issue out with DNS pretty well, it would periodically update its records in the DNS and the client actually queries the DNS to get the list of healthy servers before really contacting the server. I don't think this approach is available for openLDAP server and other platforms however I might be wrong.

More comments?

Thanks.

Kent

-----Original Message-----
From: Alan Sparks [mailto:asparks@doublesparks.net]
Sent: Wednesday, December 10, 2003 7:00 PM
To: Kent Wu (RD-US)
Cc: openldap-software@OpenLDAP.org
Subject: Re: achieve server redundancy


Well, you can do DNS round robin, creating a name with multiple A records
with each server's address.  Can be helpful.

A better way is to use a load balancing switch, like an Alteon or F5
switch.  Or look at the Linux Virtual Server project at
http://www.linuxvirtualserver.org/

Usually, you can load balance slaves effectively, but you'll need to have
a single master online to handle actual update traffic.
-Alan

> Hi guys,
>
>     Is there a way that I can set up a system with multiple LDAP servers
> so that when one LDAP server is down, the system can automatically
> direct client's request to other servers? I'm thinking if there is
> no way to set up a system like this, then probably each client needs
> to maintain a list of available servers then tries one by one to
> achieve this goal.
>
> Thanks.
>
> Kent


===========
Alan Sparks, UNIX/Linux Systems Administrator    <asparks@doublesparks.net>