Author name: Dan Langille

Yesterday I managed to move a zroot zpool from larger drives to smaller drives using snapshot, send, recv. Today, I’m doing the same thing. Yet, what is different? using serial numbers in some partition labels moving to SATADOM This really is a dry-run for when I do this on my production host, r730-01 – apart from the whole moving-to-smaller-drives part. host ssh keys NOTE: not shown in this post are messages like this:

Today, I’m going to try a test run of moving a zroot into a smaller zpool. Over the past few posts, I’ve tested moving to smaller zpools using zfs remove. That’s not what I want to do with my zpool – mostly because it does not leave you with a functioning original zpool. I’m following https://www.hagen-bauer.de/2025/08/zfs-migration-to-smaller-disk.html and I particularly like their use of labels on each partition. In this post: FreeBSe 14.3 mfsbsd-14.2-RELEASE-amd64

This is another in the series of shrinking zpools. In this test, I’m repeating the previous test, only with UEFI, not BIOS, boot partitions. Partitioning root@r730-04:/home/dvl # gpart create -s gpt mfisyspd0 mfisyspd0 created root@r730-04:/home/dvl # gpart create -s gpt mfisyspd1 mfisyspd1 created root@r730-04:/home/dvl # gpart create -s gpt mfisyspd2 mfisyspd2 created root@r730-04:/home/dvl # gpart create -s gpt mfisyspd3 mfisyspd3 created root@r730-04:/home/dvl # gpart add -t efi -s 260M -a 4k mfisyspd0 mfisyspd0p1

After succeeding with whole drives and with partitioned drives, I’m ready to try with more complex partitions. This is a repeat of the failed attempt a few days ago. Parition creation The partitions are created Create the schema: root@r730-04:/home/dvl # gpart create -s gpt /dev/mfisyspd0 mfisyspd0 created root@r730-04:/home/dvl # gpart create -s gpt /dev/mfisyspd1 mfisyspd1 created root@r730-04:/home/dvl # gpart create -s gpt /dev/mfisyspd2 mfisyspd2 created root@r730-04:/home/dvl # gpart create -s gpt /dev/mfisyspd3 mfisyspd3

After yesterday’s failure to shrink a parition-based zpool. After reading this post, you want also want to read this other successful post. You will recall that expedition ended with: dvl@r730-04:~ $ zpool add zroot mirror /dev/da2p3 /dev/da3p3 cannot use ‘/dev/da2p3′: must be a block device or regular file Today, I’m going to try the same thing with whole disks, just to see if that works. You might also want to read Moving a

Today I was setting up some drives for testing. I did this manually: root@r730-04:~ # gpart create -s gpt da2 da2 created root@r730-04:~ # gpart add -t efi -s 260M -a 4k da2 da2p1 added root@r730-04:~ # gpart add -t freebsd-swap -s 8G -a 4k da2 da2p2 added root@r730-04:~ # gpart add -t freebsd-zfs -a 4k da2 da2p3 added root@r730-04:~ # gpart show da2 => 40 62533216 da2 GPT (30G) 40 532480 1