Viewing Node settings errors out "The server cannot be reached"

Products

• CA Automic Dollar Universe

Issue/Introduction

My DUAS changes its IP address. Its DNS name is not changed. After the change I get Error "The server cannot be reached" when I click "Node Settings" from UVC. Does UVMS cache the IP address of each node? Do I need to recycle UVMS?

 

Environment

Release : 6.x

Component : DOLLAR UNIVERSE

Cause

The issue observed due to fact that the change in IP (old->new) for the Node DNS is not yet updated in DNS database. The same can be validated via nslookup utility as described below

Validation Step

1: On workstation, where UVC is launched check output of nslookp NODE_DNS.

- The expected outcome is DNS to be resolved to correct IP

 

 

Resolution

Queries

• Does UVMS caches the IP address of nodes?

UVMS doesn't cache IP's of any of the nodes

• How node DNS/hostname are resolved?

The nodes listed under Administration -> Nodes should be resolved from the workstation, where UVC is launched. The Web Console will reach the node using the DNS, then hosts file similarly as standalone UVC or Web Start, but from the server hosting the Tomcat of the Web Console.

Solution 1

• Update the DNS database to have correct mapping of DNS to IP

Solution 2

1: On the Web Console hosting server, edit file /etc/hosts file and have entry to NEW_IP HOSTNAME/DNS 

2: Login to web console and try to view the node settings of the node

Additional Information

• nslookup utility in Linux operating systems can only resolve hostnames or IP addresses that are in a DNS database and will not consider local entries in the local /etc/hosts file.
• ping utility will be resolving DNS considering entries in servers local /etc/hosts