Network Admin has changed DNS server IP address and now I have to do those changes in CUCM. I am running CUCM 9.1, I would like to know is it going to impact my licensing file or do I need to request new licenses?
This would change the license mac so a license rehost would be required. You can contact the licensing team through TAC and they would be able to help you out.
you can refer the site for LicenseMAC details.
I don't think that this changes will impact on the licenses. Because, from v9 the ELM is resonsible of license distribution.
even though please, open a case and ask the query.