Getting lot of alerts with message --object reference not set to an instance of an object

[Raviraj]

We are getting many alerts on replicate servers with below message and server goes from Monitored to Error state and within 5 secs it changes back to Monitored

53 2024-09-04 06:51:21 [ServerDto ] [ERROR] Failed to get tasks from server "Replicate': Object reference not set to an instance of an object.
5 2024-09-04 06:51:22 [Manager ] [INFO ] Executing public api AemGetTaskDetails.
5 2024-09-04 06:51:22 [Manager ] [INFO ] Executing public api AemGetTaskDetails.
70 2024-09-04 06:51:24 [Manager ] [INFO ] We got a notification. subject: , msg: Server "Replicate'' state has changed from Monitored to Error.
Message: Object reference not set to an instance of an object.

I have checked the windows event viewer for both QEM and replicate server during time error generated and cant find any issue with connectivity. 

only thing I can think of replicate is in 2021 version and QEM is 2023 , but Qlik page says its compatible

[SushilKumar]

Hello @Raviraj 

Qlik replicate 2021 version is not supported anymore. We recommend upgrading the QR version to Supported version. "Server goes from Monitored to Error state and within 5 secs it changes back to Monitored" check network and Port used in the communication are open on the Firewall for outgoing and incoming info. 

As per recommendation QR must be on Same version or major version of the QEM. or sometimes major -1. check with QR 2022 version. if it's resolved your issue.

Regards,

Sushil Kumar

[SachinB]

Hello @Raviraj ,

Thanks for reaching out to Qlik community forum.

We found a similar issue with another customer worked with their network team to resolve the issue.

We suspect there is an issue with Firewall/ACI Network between QEM and the problematic Replicate servers. Could you please check with your network and firewall team to analyze this and see if they find anything?

Lastly, we would request you to create support case and please provide below information on case we will take it ahead.

1) Form your QEM expand the Message Center by clicking on the arrow, set filter to all and provide a screen shot.
2) Then please click on Servers tab and open up the problematic replicate by double clicking it and then uncheck "Monitor this server's tasks and messages" and test again.

Regards,

Sachin B

[sureshkumar]

Hello @Raviraj 

I would suggest Go to Server-->Stop Monitoring and then enable Start Monitoring and observe the behavior.

Regards,

Suresh