NiFi. QueryDatabaseTable - failed to retrive observed maximum values from state manager. will not perfom query until this is accomplished

[#1]

Hi guys! In the QueryDatabaseTable processor configuration, the Maximum-value Columns parameter specifies a column from the database table. The database polling frequency is 5 seconds, but it happens that new data in the table does not have time to appear after 5 seconds and probably due to this the following error appears, but the processor is working and when data appears, it takes it, but this error annoying, can it be avoided somehow?

[#2]

@Wadok88, Welcome to our community! To help you get the best possible answer, I have tagged in our NiFi experts @cotopaul @MattWho @SAMSAL @steven-matison  who may be able to assist you further.

Please feel free to provide any additional information or details about your query, and we hope that you will find a satisfactory solution to your question.

[#3]

@Wadok88,

The problem you are reporting is not related to the database and how it works, but to how you configured your NiFi Instance and especially your ZooKeeper.

First of all, are you using embedded Zookeeper or external Zookeeper ? Did you configure the state-management.xml file and the nifi.properties file with the correct connection string for your Zookeeper nodes?

Secondly, when using NiFi in a cluster manner, the Zookeeper is used to maintain the state of some processors within the entire cluster, meaning that those processors will try and attempt to use the state manager, even though it was not configured -- or in your case not configured correctly.

So what I suggest you to do is check the zookeeper configurations from within NiFi. Next, set you processor on debug and check if NodeX is able to retrieve the state using the ZK and so on. Maybe you have a connectivity issue from a specific node.

[#4]

@Wadok88, Has the reply helped resolve your issue? If so, please mark the appropriate reply as the solution, as it will make it easier for others to find the answer in the future.