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IP/DNS could not be resolved during vSphere Data Protection (VDP) 5.1.x installation (2036396)


Configuring vSphere Data Protection (VDP) 5.1 from the URL https://IP_address/name:8543/vdp-configure fails with the error:
IP/DNS could not be resolved. Please re-check the hostname, domain and DNS values for forward and reverse lookup validation


This issue occurs when Fully Qualified Domain Names (FQDN), forward lookup, and reverse lookup are not configured, or they are not configured correctly. This issue can also occur if TCP connectivity to DNS server is blocked on port 53.


To resolve this issue, you must configure a DNS host record before deploying a vSphere Data Protection (VDP) appliance. Make sure you have configured your DNS server for the VDP appliance with a pointer for mapping the IP address to the VDP appliance, and that it is created according to your vendor's specifications.

For more information, see the vSphere Data Protection Administration Guide.

Note: A TCP connection to DNS is required by VMware proxy nodes via port 53.

A Fully Qualified Domain Name (FQDN), as well as forward and reverse lookup, must be configured correctly for VDP to work. A failure to configure these correctly impacts VDP operations (such as backups).

For more information, see vSphere Data Protection (VDP) FAQ (2016565).

Also, run these commands from both vCenter Server and the VDP appliance to verify that DNS is properly configured:
  • nslookup FQDN_of_vcenter DNS_Server
  • ping FQDN_of_vcenter DNS_Server
  • nslookup IP_of_vcenter DNS_Server
  • ping IP_of_vcenter DNS_Server
  • nslookup IP_of_VDP DNS_Server
  • ping IP_of_VDP DNS_Server
You may also want to perform the lookup on short names.

Additionally, you may add the default domain and the search domain to the /etc/resolv.conf file.

To add the default domain and the search domain to the /etc/resolv.conf file:
  1. Open the /etc/resolv.conf file using a text editor.
  2. Add these entries to the file:

    • domain XXXX.XXX
    • search XXXX.XXX
    • nameserver YYY.YYY.YYY.YYY
Note: FQDN validation is case sensitive. If you enter uppercase or mixed case names and DNS returns it in any other way, the test will fail.

See Also

Update History

10/24/2012 - Add a pointer for DNS 10/30/2012 - Updated DNS and FQDN for nslookup and ping 04/02/2013 - Added information on port 53.

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