An administrator encounters domain session cookie resolution issues during authentication with Citrix ADC. Which DNS configuration fixes this issue?

• A. Configure DNS to assign authentication and traffic management vServers to FQDNs in the domain.
• B. Configure FQDNs for the Session Cookies in the domain.
• C. Change the Session Cookie timeout in DNS.
• D. Configure DNS to assign an FQDN for the Citrix ADC in the domain.

Answer: (A)

DNS mapping of authentication and traffic management vServers to domain FQDNs ensures that cookies used during domain authentication resolve to the correct targets. When users authenticate, the session cookie is tied to the DNS name of the vServer handling that session. If the vServers aren’t published under domain-level FQDNs, DNS can resolve inconsistently or to different hosts, causing the cookie to fail to be recognized or reused on subsequent requests. By configuring the domain so that both the authentication vServer and the traffic management vServer have explicit FQDNs in the domain, the cookie’s host portion matches the DNS name the client uses, enabling proper cookie delivery and session continuity across requests.

The other options don’t address the root cause. Simply configuring FQDNs for the cookies themselves doesn’t fix how DNS resolves the vServers involved in the authentication flow. Changing the session cookie timeout is about cookie duration, not how DNS routes or resolves the session, and assigning an FQDN for the Citrix ADC alone doesn’t ensure the authentication and traffic management vServers resolve consistently to the same domain.