Question

Node is down

Hi Team,

We configured 3 nodes on which 5 Agents are running.But some times we get an issue that the node is not getting picked.We can see that the agents are running on that node but they are not getting picked

So can you please help to resolve the issue

***Edited by Moderator: Lochan to update platform capability tags***

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November 27, 2019 - 1:39pm

I don't fully understand the issue.

1. Is the node running?

2. What is meant by "the node is not getting picked"?

November 28, 2019 - 12:17am
Response to CarissaW_GCS

Hi Carissa,

The  3 nodes and 5 agents on that node are running.We configured Connect-Rest to send policy details to external system through agents.But the details are not sent to external system from one node,while the details are send through other node.This issue is not with agents and service as it is working fine in other node.

Can you please help us to find out where can be the issue

Pega
November 28, 2019 - 10:34am

Hi Asma,

Please verify pr_sys_statunodes table, Pega nodes are registered into the table pr_sys_statusnodes at startup time, This table holds information such as the node IP address, node name, etc.

When a node joins the cluster, a list of cluster-member candidates is loaded from the pr_sys_statusnodes table. The node, then, tries to establish a connection with the candidates to form a cluster. Please verify status of each node, it should be either running or stopped.

Thanks,
Abhinav

November 28, 2019 - 8:14pm

Hi Asma,

 

Which version of Pega you are using?

If you are using Pega v7.3.1 and above, there is a concept of node type.

If you have defined node types for different nodes and the agent is supposed to be running on some specific node type(for example webuser or background processing), then it will not be running in the rest of the nodes (having different node type).

Could you please attach the complete agent configuration.

Also attach the screen-shot of the cluster information of your environment from Designer Studio.

 

Regards,

Vikash

November 28, 2019 - 11:37pm
Response to Vikash Karn

Hi Abhinav,

My pega version is 7.3.1

Agents are configured as below:

There are 3 nodes and 5 agents which are configured as "RunonAllNodes" node type.These 5 agents will be running on all nodes.Also there are other 3 agents which are configured as "BackGround" Processing.

Cluster Information is as below:

2 nodes are configured with node type as "Webuser" and 1 node as "Backgroundprocessing"

But the issue is not constant.It is intermediate.When I save the agent rule again in higher ruleset version eveything works fine.

 

I am not sure whether I can provide any screen shots as per business needs 

November 29, 2019 - 12:31am
Response to Asmas876

The 3 agents which are configured to run on backgroundprocessing node will be running only on background node.

For the rest 5 agents which are configured to run on all nodes, do you have Run this agent on only one node at a time checkbox checked?

November 29, 2019 - 1:55am
Response to Vikash Karn

Hi ,

The checkbox is not checked.All 5 agents will run on all nodes.Also the locking is handled by using parameters.

 

December 2, 2019 - 7:10am
Response to Asmas876

Hi Vikas,

Did you find any issues in our node configuration,so that this issue has occured

 

December 2, 2019 - 8:17pm
Response to Asmas876

Hi Asma,

 

When the agent doesn't run on a particular node do you see either the last runtime or next run time of the agent empty in that node?

 

December 2, 2019 - 11:47pm
Response to Vikash Karn

Hi,

All agents are running fine.There is no empty field in time

December 3, 2019 - 12:02am
Response to Asmas876

Did you check the Pega-RULES logs for any agent failure message when the agents didnt run on a particular node?

 

Pega
November 29, 2019 - 12:36am

Hi Asma,

Please verify pr_sys_statusnodes table & let me know the status of each node.If any node is in stop status then we need to analyse logs of that node.There will be some error in logs.

Thanks,
Abhinav

November 29, 2019 - 1:59am
Response to Abhinav7

Hi Abhinav,

I don't have access to DB to check this table.Please let me know any other option from where I can check this

 

Pega
November 29, 2019 - 11:17am
Response to Asmas876

Hi Asma,

You can ask your DB team to get the required details. You can use OOTB query runner also.

Thanks,
Abhinav

December 2, 2019 - 12:06am
Response to Abhinav7

Hi Abhinav,

But now all nodes are working fine when the agent is saved to higher ruleset version.So all nodes will be in running state.

How can use this OOTB query runner.Please provide complete steps

Pega
December 2, 2019 - 1:19am
Response to Asmas876

Hi Asma,

Please follow below steps to configure query runner.

1.You need to have PegaRULES:PRPCDatabaseAdministrators role to run the query from the query runner landing page.If you do not have the role you can add the role by opening your current accessgroup.

2.Click on DesignerStudio --> System --> Database --> QueryRunner to navigate to Query Runner landing page

In case you are on Pega 8 click on Configure -- > System --> Database --> Query Runner

3. Select the database which you want to query upon from the dropdown.

4. Write the query which you wanted to run. (Note- The query should contain fully qualified name of the table).

5.Click on run button.

 

Thanks,
Abhinav

December 2, 2019 - 1:22am
Response to Asmas876

Incase you do not have access to DB, you can do any of the following to look at the contents of the table.

1. Create a simple activity with Obj-Browse on class "System-Status-Nodes". This will bring all the entries present in the table.

2. In App Explorer, navigate to class "System-Status-Nodes" and look at all the instances present.

December 2, 2019 - 1:52am

Hi Asma,

The Query Runner is available for Pega Cloud customers who use a Postgres database or for customers using an Oracle database on-premises or in the Pega Cloud.

So if you are not on Pega-Cloud using Postgre or you are not using Oracle DB then query runner will not work for you.