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Joined 1 year ago
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Cake day: July 16th, 2025

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  • Well, Im trying it with the 2 raidz of 4 disks. but now, other questions emerged

    1. NFS or iSCSI Considering that my enviroment is composed by XCP-NG hosts and a ZFS pool of 2 vdevs with 4 disks, what would be the pros and cons of chossing NFS (file-based) or iSCSI/Zvol (block storage SR)? I’m concerned about the high density of VDIs and IOPS on a sync writes. The server has an adequate amount of ram (64GB)

    2. mitigate the sync writes. XCP-ng, one of my vm manager (other is going to be KVM), by default, usually force sync writes to garatee VM integrity. That could be bad for the performance of this SAS 7200RPM disks. I don’t have, at least for now, a good solid state drive to help, but maybe some tuning on the sync on the ZFS could help? (sync=always vs sync=standard vs sync=disabled)

    3. ZFS volume tuning I set up my ZFS pool with ashift=12 (4K) and recordsize=128k. If i choose for iSCSI creating ZVOL volumes, what should be the ideal volblocksize?

    4. Backup and snapshot Right now I have a pretty big archived old VMs and snapshots. I wonder what would be more efficient for backup and recovery. Use zfs snapshot and tools for backup or use the orchestrator on XCP-NG?