Which two statements are true for mailbox disks per node in an HA pair? (Choose two.)
Which two statements are true for mailbox disks per node in an HA pair? (Choose two.)
Four disks are required if the root volume is on a mirrored aggregate. One array LUN is required if the root volume is on a storage array. These statements are accurate because in a SyncMirror configuration involving HA pairs, each node typically has four mailbox disks if the root volume is mirrored. Additionally, for storage arrays, only one array LUN is needed for the root volume.
The question from Netapp is choose 3 and the answer is B, C, and E
while I agree with B and E I also found this: In a SyncMirror configuration, the MB disks are mirrored. An HA-Pair deploying SyncMirror will have eight MB disks, four per node, assuming the root aggr/volume is mirrored and consists out of at least two disks.
C & E https://kb.netapp.com/app/answers/answer_view/a_id/1003013/~/what-is-a-mailbox-disk%3F- The storage system always selects the parity disk and the first data disk of the root aggr/volume to be the two mailbox disks in a RAID4 configuration. If the aggr is Raid_DP, then the Parity and the D-Parity disks are selected. In a SyncMirror configuration, the MB disks are mirrored. An HA-Pair deploying SyncMirror will have eight MB disks, four per node, assuming the root aggr/volume is mirrored and consists out of at least two disks.
B, E Mailbox disks or array LUNs on the root volume Two disks are required if the root volume is on a disk shelf. One array LUN is required if the root volume is on a storage array. https://docs.netapp.com/ontap-9/index.jsp?topic=%2Fcom.netapp.doc.dot-cm-hacg%2FGUID-F7A9F512-4163-41AD-9DB3-E24C071EC99A.html
B and C https://kb.netapp.com/app/answers/answer_view/a_id/1003013/~/what-is-a-mailbox-disk%3F- "The storage system always selects the parity disk and the first data disk of the root aggr/volume to be the two mailbox disks in a RAID4 configuration. If the aggr is Raid_DP, then the Parity and the D-Parity disks are selected. In a SyncMirror configuration, the MB disks are mirrored. An HA-Pair deploying SyncMirror will have eight MB disks, four per node, assuming the root aggr/volume is mirrored and consists out of at least two disks."
Sorry, I think it is C and E: "In a non-mirrored HA-Pair: The node usually has two MB disks (exception: V-Series might only have one if the root aggr is consisting out of one LUN only). If one of these two MB disks fails, the takeover will be disabled. The MB states are verified and once another MB disk has been selected, takeover will be enabled. In a SyncMirrored configuration: The node usually has four MB disks, two local and two remote (exception: V-Series might have only two, one local and one remote if root aggr consists of one LUN only). If one plex containing two MB disks fails, takeover will be disabled. MB states are checked and these disks are removed from the MB disk set. Takeover will then be enabled."