VNA install fails with 404 errors and problem creating domain

Products

• CA Virtual Network Assurance
• DX NetOps

Issue/Introduction

We are trying to install VNA 20.2.10 on RHEL 7.9 VM. We are getting below error while running the installer:

WARNING: Unable to create the default user domain: 404. Please check the logs in /vna/CA/VNA/wildfly/standalone/log.
WARNING: Unable to create VNA UI user: 404

Installing Virtual Network Assurance (VNA) the following errors are seen at the CLI. First we see the already noted 404 error above. After that we see this DNS Error message.

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<big>DNS Error (dns_unresolved_hostname)</big>
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Your requested host "localhost" could not be resolved by DNS. Please make sure you typed the URL correctly.
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That ends with the following references to seek assistance in resolve the problem.

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For further assistance, please contact your respective Component Help Desk and/or Component SOC.
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 <font face="Arial, Helvetica, sans-serif" size="2" color="Silver"><b>Proxy: PROXY_HOST_NAME<br> Your IP address: 1.2.3.4 <br>RH:curl&#x2F;7.29.0<br> HTTP1.1 <br></b></font>
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Additional information may be found <A HREF="http://dhsconnect.dhs.gov/HELP/Pages/HelpDesks.aspx">here.</A>
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If you would like to submit for access to a blocked page submit a <A HREF="https://internal_URL.com/">Web-Request.</A>
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Lastly the install exits showing:

 Error installing plugin: /vna/installs/CA_VNA_Install/openstack-plugin-20.2.10-RELEASE.jar - 404. Please check the logs in /vna/CA/VNA/wildfly/standalone/log.
A problem occurred during installation (install directory not deleted). Backing up to /vna/installs/CA_VNA_Install_bak

Environment

All supported DX NetOps Virtual Network Assurance (VNA) releases

Cause

An http proxy in the environment is rejecting calls for localhost on the VNA host required by the installation.

To validate this is the cause run the following command on the VNA server. If if returns configured proxy hosts it is the cause of the problem.

echo $http_proxy

Resolution

To resolve this problem we'll need to use one of these options.

1. Unset the proxy configs.
   1. To do this we'd run the command on the VNA server:
      1. unset http_proxy HTTP_PROXY
   2. Run the VNA installer again
2. Disable proxy host usage for localhost requests.
   1. To this we'd run the command on the VNA server:
      1. export no_proxy=localhost,<machine hostname>
      2. Replace <machine hostname> with the VNA server hostname
   2. Run the VNA installer again