1Y0-A26 · Question #114
An administrator CANNOT use XenCenter to connect to an existing standalone XenServer host that has six virtual machines running. What could be causing this issue?
The correct answer is B. The XAPI Service stopped. See the full explanation below for the reasoning.
Question
An administrator CANNOT use XenCenter to connect to an existing standalone XenServer host that has six virtual machines running. What could be causing this issue?
Options
- ANTP is NOT configured.
- BThe XAPI Service stopped.
- CThe XenServer DNS configuration is incorrect.
- DCommunication with Active Directory has been lost.
How the community answered
(50 responses)- A4% (2)
- B76% (38)
- C6% (3)
- D14% (7)
Community Discussion
8
Nina C.Jan 30, 2026The correct answer is B, the XAPI service stopped. XAPI is basically the management brain of XenServer, it is the API layer that XenCenter talks to when it connects, so if that service goes down, XenCenter has nothing to communicate with and the connection fails. The important thing to notice in this question is that six VMs are still running, which tells you the host itself and the Xen hypervisor are fine, only the management layer is gone. The other options like NTP, DNS, or Active Directory could cause headaches in other scenarios, but none of them would completely block a XenCenter connection to a standalone host the way a stopped XAPI service would.
Mei-Ling H.Jan 1, 2026The answer is B because XenCenter uses the XAPI (XenServer API) service to connect and manage hosts, so if that service stops, XenCenter has no way to communicate with the host at all, even though the VMs stay running. Notice the question says "standalone" host, which rules out D since Active Directory is not required for a standalone setup.
Dervla O.Jan 1, 2026Good catch on the standalone detail, but worth noting that the real elimination logic here is process of elimination on what keeps running versus what loses its management plane, since the VMs persisting is the key distractor designed to pull you toward the infrastructure answers.
Grace U.Jan 19, 2026Went straight to C, then remembered XAPI is the whole connection layer.
Isolde G.Jan 7, 2026I initially went with C because DNS misconfigs are such a common culprit when you cannot reach a host by name, but then I remembered that XenCenter can connect via IP address too, so DNS alone would not block you entirely, whereas XAPI is the entire management API stack and if that service is down, nothing on XenCenter can talk to the host regardless of how you address it.
Dervla O.Jan 8, 2026Good catch on XAPI, and to sharpen the edge on your DNS point, a name resolution failure would still surface as a connection error in XenCenter rather than a clean authentication or management-plane fault, which is one more reason to chase the service layer first.
Dervla O.Feb 4, 2026My gut went straight to C on the first read, because DNS problems are behind a huge chunk of "can't connect" scenarios in real environments and the stem mentions a standalone host which signals potential network config gaps. But then I read the stem a second time and caught the detail that all six VMs are still running, which tells you the hypervisor layer is fine and the network is reachable enough for traffic to flow. That detail is the eliminator. XAPI is the management plane service that XenCenter talks to, so if XAPI dies, the connection fails completely while the VMs keep humming along underneath on the Xen layer, which fits the scenario exactly. A and D fail fast because NTP and Active Directory gaps create authentication or time-skew friction, not a hard block on XenCenter connectivity to a standalone host with no domain dependency mentioned.
Nina C.Feb 6, 2026Good catch on the standalone detail doing that double duty, though I would add that DNS is not fully off the table even on a standalone host if XenCenter is resolving by hostname rather than IP, so the VMs-still-running clue is really what closes the door on C and locks in XAPI as the only fit.