Issue to replicate modifications on both servers in load balancer configuration

nbisoft

30-10-2018

Hi,

Our system is configurated in load balancing with 2 servers.

Everything is working fine (connections...) except that we have issues to replicate modifications on both servers at the same time. For example, if we add a new field and do an update on our oracle database, depending on the server we are actually connected, we could have an error showing that the new field does not exists. The error disapear completely only if the application is restarted the next day. So, if the restart is not done we have the error showing each time we are trying to access the new object.

Thanks in advance for your help,

Nbe

Accepted Solutions (1)

Accepted Solutions (1)

Vapsy

Employee

06-11-2018

Hi nbisoft,

It is a known behavior and design for Campaign.

When you make schema modifications, frontal servers actually keep an XML copy of all schemas on the File System.

Not all servers will get the new copy.

Anything which goes into the database will be readily available to all servers but anything picked from File System will not.

So, you will have to work with a change management plan.

Whenever rolling out a new change to the schema, please ask the server team to restart web module for both servers. There will be a downtime of 5-9 seconds but since the connection is load balanced, they can

1. Take server 1 out of LB

2. Restart web on server1

3. Add server1 back to LB and take out server2

4. Restart Server2 web module

5. Add server2 back to LB

Regards,
Vipul

Answers (2)

Answers (2)

Adhiyan

Employee

06-11-2018

Hello ,

Can you please share a bit more detail about the architecture.

1>. Do you have 2 app servers connected to a single DB

2>. 2 app servers connected to two different databases.

The issue should not happen if you have the config like 1

Regards,
Adhiyan

nbisoft

07-11-2018

Hello Adhiyan and Vipul,

Thanks for the feedback.

Vipul Raghav​, is it compulsory to remove server from LB before restarting the web? Actually, we have tried restarting the web module and it did not help the situation. Is there any other easy mean to correct the issue?

Regards,

Nbe