csm-s maxconns and backup serverfarm

[Jon Marshall]

Hi all

We have a situation here at work where we are about to significantly increase the number of users going through our load balancers (csm-s version 2.1(4) ).

The application guys have asked whether there is a way to limit the number of connections allowed and if that limit is exceeded then send users to a different server with a "application busy" type error page. Not ideal but it will be a while before they can upgrade their infrastructure. i have a few quick questions.

1) If i have a maxconns limit under the vserver config and that limit is reached does it then use a defined backup serverfarm.

2) if the maxconns is reached and the CSM-S uses the backup serverfarm, are the real servers marked as out-of-service. If so presumably they are put back in service once the number of connections falls below the maxconns limit.

3)If the reals are marked out-of-service will existing user connections be serviced (they will be using sticky).

4) Is there a better way to do this with the CSM-S

Any help much appreciated

[Gilles Dufour · Accepted solution]

I would suggest the maxconn per server.

Each server that will reach the maxconn will be put out-of-service until the number of connections drop.

If no more servers are active, than a backup serverfarm will be used if it has been configured.

Connections active with a server are not affected when this server goes out-of-service.

This is the only way to achieve what you want.

Gilles.

[Jon Marshall]

Many thanks Gilles