1Y0-A26 · Question #112
Scenario: An administrator CANNOT use XenCenter to manage an existing XenServer host in a resource pool. The administrator found that the XenServer host CANNOT communicate properly with XAPI. What…
The correct answer is A. Dom0 is out of space. See the full explanation below for the reasoning.
Question
Scenario: An administrator CANNOT use XenCenter to manage an existing XenServer host in a resource pool. The administrator found that the XenServer host CANNOT communicate properly with XAPI. What could be causing the communication issue on the failed host?
Options
- ADom0 is out of space.
- BNTP is NOT configured.
- CThe root password is unknown.
- DThe host CANNOT connect to Active Directory.
How the community answered
(27 responses)- A78% (21)
- B11% (3)
- C7% (2)
- D4% (1)
Community Discussion
4
Giovanna H.Mar 12, 2026This one maps to the XenServer Architecture and Management domain, specifically the XAPI service health section. Mnemonic to keep handy: SPACE KILLS XAPI, meaning a full Dom0 filesystem is one of the first things to rule out when XAPI becomes unresponsive. The correct answer is A, Dom0 is out of space. XAPI writes logs, databases, and state files to Dom0, and when that filesystem fills up, XAPI cannot function, which breaks XenCenter connectivity entirely. The other options can cause various management issues but do not directly starve XAPI of the disk writes it needs to stay operational.
Wesley A.Mar 15, 2026That mnemonic is solid and I wish I had it my first attempt, though I would add that checking "df -h" on Dom0 should be step one in any XAPI triage, before you even bother restarting the service.
Imani T.Feb 25, 2026Dom0 full kills XAPI, but what fills it up fastest in your experience?
Wesley A.Mar 4, 2026Saw almost this exact scenario on my exam and I almost talked myself into B because I had just been reading about NTP causing pool join failures the night before, but then I remembered that XAPI logs and its socket files live in Dom0 and when that filesystem fills up the daemon cannot write anything and just silently breaks, which is exactly the "cannot communicate with XAPI" symptom they are describing. A is your answer, do not overthink it.