How to configure QlikView for FailOver and Resilience

[ilyas393]

Hello Experts,

We have a cluster of 3 servers for QVS.

• On Server 1, we have QVS, QVWS, and QDSC
• On Server 2 and 3, we have QVS and QDSC

When Server 1 goes down, or becomes inaccessible, the AccessPoint becomes unavailable and the users are not able to get to their dashboards.

How can I make Server 2 and 3 as a failover for Server 1 so that if Server 1 goes down, the access point is still available?

Should I have QVWS on all the three servers? what is the right approach?

Appreciate any help.

Thanks,

Ilyas

[Miguel_Angel_Baeyens · Accepted solution]

Having a web server in each server will definitely help in balancing the load as well as make sure the AccessPoint is not a point of failure.

It's frequent that those different webservers are behind a proxy or load balancer that provides the user with a single URL, regardless which ones or how many are available.

Note that when using the Ajax client, every user must access the webserver first, and the webserver will establish the connection with the QlikView Server (while using Desktop > File > Open in Server and IE Plugin users connect directly to the node specified, which in general is not recommended).

[ilyas393]

Thank you for your response. If I have the webserver (QVWS) on multiple servers that also has the QlikView Server (QVS), do I need to have a third-party load balancer for the webservers? Is this the only option? Do you know if QlikView also has this inbuilt ?

I appreciate your response.

[cwolf]

What do you mean with QDSC? QlikView Distribution Service (QDS) or Directory Service Connectors (DSC)?

A DSC is needed for QDS and QVWS, the QVS self doesn't need a DSC;

A QDS you should never install on a QVS node!

A QVWS does not have such a high load that a third-party load balancer (which would be the only option) would warrant it.

Install QVWS and DSC on a separat virtual server. A virtual environment offers sufficient availability and reliability for a QlikView web server.

All in all I think you will get maximum on performance, availability and reliability with the following constellation:

Server 1,2,3: QVS
Server 4 (virtual): QVWS, DSC
Server 5 (physical or virtual): QMS, QDS, DSC

[ilyas393]

Right now we have only one QVWS which is on the same server as one of QVS service. If this server goes down, then the accesspoint becomes unavailable. I am trying to setup a fail-over for the QVWS server.

So if I have QVWS on multiple servers (say server1 and server2), then each access point has its own URL (like https://server1/qlikview and https://server2/qlikview). So if server1 goes down, the users can log onto server2 manually and vice-versa. I need to make this switch seamless for our end users.

Once option is to use a third-party load balancer. Is there any other way?

Thank you for your response

[Brett_Bleess · Accepted solution]

The only other option would be a DNS alias pointed to one of  the QVWS instances and if that instance goes offline, the network team changes the alias to point to one of the other QVWS services, but this will result in downtime for sure, whereas having a Network Load Balancer in front of the QVWS instances will result in an always available situation and Qlik does NOT offer Network Load Balancing in the QVWS product, you would need to purchase one.

Regards,
Brett