I'd like to ask for your help in order to validate a design of mine concerning the deployment of two Cisco CSS 11503 switches for load balancing, failover, and high availability.
Currently I am at the very first phase of this deployment and the layer 2 parameters of both CSS switches have already been configured and it is fully functional. The next step will be the load balancing and failover scenarios and I've a question about whether it can be done or not.
Please review the attachments in order to understand what the scenario deployment looks like.
The scenario description is as follows:
- There are two Cisco CSS 11503 switches
- There are three backend Servers
- These servers run the end customer application + an Oracle (Timesten) database
- Each server has the same content and the Oracle databases are fully synchronized
So how things are supposed to work? Let's see:
1) The high availability between the two Cisco CSS will be Active/Standby. This includes VIP redundancy and Virtual Interface Redundancy
2) The end users will communicate with the VIP that represents the application, initiating the connections to that VIP.
3) The active CSS will handle the request from the end user and will load balance (round-robin) the requests to one of the three available servers.
4) The server on the other hand will initiate a connection to the database, which might be its own copy of Oracle/Timesten or not (it depends on which of the three servers is holding the âmasterâ role).
5) So, therefore, the connection from the application to the database will be made through a second VIP and the Cisco CSS 11503 switches must NOT load balance in this case, since it could corrupt the entire database.
The following summarizes what we need to accomplish our goals: there will be two VIP addresses (one for the application and the second for the database), loadbalancing for the application VIP only, failover for the database VIP, and virtual redundancy to provide the servers with default gateway high availability.
I'm enclosing the initial configuration. I still need to insert the rest of the configuration parameters to fulfill my project's objectives. In order to do that, my questions are:
- How can I prevent the CSS switches from load balancing the requests from the application to the database? Load balancing must NOT occur as per the design's requirements.
- Since load balancing cannot be done, how would the CSS switches provide failover services in case of issues with the database on the master server?
I look forward to hearing from you soon.
Big thanks in advance!!