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On 13 Jun 2001, Andreas J. Koenig wrote:
> >>>>> On Mon, 11 Jun 2001 20:47:49 +0200 (METDST), Alois Treindl
> >>>>> <alois@xxxxxxxx> said:
>
> > I have created a patch for ldirectord.
> > The purpose of the patch is to solve this problem:
>
> > my set of http servers is tightly bound with a mysql database server;
> > the interactive website does not work if the DBMS is not available.
>
> I have argued in a different thread on the lvs list that this is your
> application's fault. Your application must be able to respond to the
> failure of a dependency. If it did, you could easily use ldirectord to
> fulfill your needs.
My LVS cluster depends totally on the availability of one key server,
because besides the DBSM the web servers also mount all their www data
and executables via NFS from a central server.
If that key server w1 is down, no operation of the 'slave servers' is
possible, not even a single http response.
I think that this kind of dependency should be reflected in information
present in ldirectord, which determines what is visible of the LVS
services to outside clients, and NOT left to the various real servers
on the application level.
besides this, our website does only serves dynamic content originating
from a database server; it would be much more complex to make all
real server capable of keeping up replying when the the dbsm is down, than
to declare them 'off' via the director.
Whether my proposal makes it into an official edition of ldirectord
is not really my concern. I am perfectly happy to keep it as my
private patch. The way I have implemented it makes it rather
simple to re-apply it to any future edition of ldirectord, if I should
ever choose to upgrade.
Alois
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