vCenter sending incorrect DNS requests of non-existants hosts

[stephentzsamal]

vCenter is in an A/D domain:

corp.pvt

vCenter DNS suffix search order is:

corp.pvt

corp.local

corp.com

ESXi hosts are all resolvable using:

corp.com

ESXi hosts are added to vCenter inventory as host.corp.com

From vCenter, host.corp.com is resolvable, no issues.

When looking at DNS request packet traces from our vCenter, instead of requesting for one request (host.corp.com - they way it was added in its inventory) it's always trying all three in the order of the suffix search, i.e.:

host.corp.pvt (results in bad request)

host.corp.local (results in bad request)

host.corp.com (finally gets a positive return)

This has no impact to vCenter/Host connectivity, just trying to understand and potentially get an explanation as to why vCenter would behave like this if the FQDN was provided for the host?

Thanks

[LucianoPatrão]

Hi,

First always add information about VMware versions(vCenter, vSphere, etc.) It helps providing the proper solution.

Are this domains all locally? Or this are main domain(like enterprise) what is working, then the sub/domains are remote locations that are not working?

You could add hosts / domains in the host file so that you can resolve all.

How to:

Identifying issues with and setting up name resolution on ESX/ESXi Server (1003735) | VMware KB

https://kb.vmware.com/kb/1003713

Hope this helps.

[stephentzsamal]

vcenter version is 5.5

its not a question of working or not working.

its a question of behavior.

Host was added as "host.corp.com"

Based on DNS packet traces, vCenter is not sending a DNS request for "host.corp.com" it is instead stripping ".corp.com" taking only the "hostname" and then appending each domain in the Suffix Search Order list (from Windows TCP/IPv4 DNS configuration):

"host.corp.pvt" --- WRONG

"host.corp.local" --- WRONG

"host.corp.com" --- CORRECT!

Why doesn't it just use the FQDN that it was provided?