So, when building my new plexguide server, it was important that my old server kept running during the setup, configuration and migration period. So I installed ubuntu 18.04 and plexguide on an old small server that I had laying around. This metal was just temporary, so it's size did not matter much. As long as it had room for some old spare harddisks I could use as staging area for my data.from a clean install of plexguide, i then did thisin part adopted from here:apt-get install parted gdiskfdisk -lshows our old 7 4TB disks and that they are identified as sda sdb sdc sdd sde sdf sdgsdh was boot disk. So we won't touch that one.lets partition one of the data disks, and then save the layout and use it for the other datadisksparted -a optimal /dev/sdamklabel gptmkpart primary 1 -1align-checkoptimal1 (partition number)quitbackup the partition table for reusesgdisk --backup=table /dev/sdareuse the partition table on the other 6 diskssgdisk --load-backup=table /dev/sdbsgdisk --load-backup=table /dev/sdcsgdisk --load-backup=table /dev/sddsgdisk --load-backup=table /dev/sdesgdisk --load-backup=table /dev/sdfsgdisk --load-backup=table /dev/sdgNow, we will make a place to mount the disks. I mount them via /etc/fstab labeled by their device type and serial number as seen below. This makes the disk easier to identify in the event of a disk failure.mkdir -p /data/{disk1,disk2,disk3,disk4,disk5,disk6,disk7}mkfs.ext4 -m 0 -T largefile4 /dev/sda1mkfs.ext4 -m 0 -T largefile4 /dev/sdb1mkfs.ext4 -m 0 -T largefile4 /dev/sdc1mkfs.ext4 -m 0 -T largefile4 /dev/sdd1mkfs.ext4 -m 0 -T largefile4 /dev/sde1mkfs.ext4 -m 0 -T largefile4 /dev/sdf1mkfs.ext4 -m 0 -T largefile4 /dev/sdg1ls -la /dev/disk/by-id/ | grep part1 |grep -v wwn | cut -d " " -f 10-20give us something like thisata-ST4000DM000-1F2168_Z300C7D2-part1 -> ../../sdg1ata-ST4000DM000-1F2168_Z300CS64-part1 -> ../../sdf1ata-ST4000DM000-1F2168_Z300CSLE-part1 -> ../../sde1ata-ST4000DM000-1F2168_Z300CW2K-part1 -> ../../sda1ata-ST4000DM000-1F2168_Z300D1Z3-part1 -> ../../sdd1ata-WDC_WD40EFRX-68WT0N0_WD-WCC4E6NZX05P-part1 -> ../../sdc1ata-WDC_WD40EFRX-68WT0N0_WD-WCC4E6RY2RV4-part1 -> ../../sdb1use it when editing fstabvi /etc/fstabthe end result of the new lines should look something like this + whatever was there to start with/dev/disk/by-id/ata-ST4000DM000-1F2168_Z300C7D2-part1 /data/disk7 ext4 defaults 0 2/dev/disk/by-id/ata-ST4000DM000-1F2168_Z300CS64-part1 /data/disk6 ext4 defaults 0 2/dev/disk/by-id/ata-ST4000DM000-1F2168_Z300CSLE-part1 /data/disk5 ext4 defaults 0 2/dev/disk/by-id/ata-ST4000DM000-1F2168_Z300CW2K-part1 /data/disk1 ext4 defaults 0 2/dev/disk/by-id/ata-ST4000DM000-1F2168_Z300D1Z3-part1 /data/disk4 ext4 defaults 0 2/dev/disk/by-id/ata-WDC_WD40EFRX-68WT0N0_WD-WCC4E6NZX05P-part1 /data/disk3 ext4 defaults 0 2/dev/disk/by-id/ata-WDC_WD40EFRX-68WT0N0_WD-WCC4E6RY2RV4-part1 /data/disk2 ext4 defaults 0 2As you may be able to see, the above shows the type of connection, in this case SATA, the Manufacturer of the disk, the part number of the disk, the serial number of the disk, and the partition we are using from the disk. This makes indentying disks in the event of a failure super easy.mount the new filesystemsmount -adf -h/dev/sdg1 3.7T 89M 3.7T 1% /data/disk7/dev/sdf1 3.7T 89M 3.7T 1% /data/disk6/dev/sde1 3.7T 89M 3.7T 1% /data/disk5/dev/sda1 3.7T 89M 3.7T 1% /data/disk1/dev/sdd1 3.7T 89M 3.7T 1% /data/disk4/dev/sdc1 3.7T 89M 3.7T 1% /data/disk3/dev/sdb1 3.7T 89M 3.7T 1% /data/disk2nice, now we have 7 4TB staging disks. But we really need to present them as 1 concatenated filesystem in order for plexguide to understand it. I could probably have used plexguides unionfs (as it does the same thing as mergerfs). But I don't know the inner workings of plexguide, so I opted for mergerfs instead. Keeping things separated.Guide adopted from here. This is also where you will find guide to compile from source if needed.this is mergerfs githubnow we are ready.pick the newest for you os and downloadwget https://github.com/trapexit/mergerf....25.1/mergerfs_2.25.1.ubuntu-xenial_amd64.deb install itdpkg -i mergerfs_2.25.1.ubuntu-xenial_amd64.debclean uprm mergerfs*.debcreate the directory for the concatenated mountmkdir /storageadd the mount to /etc/fstab/data/* /storage fuse.mergerfs defaults,allow_other,direct_io,use_ino,category.create=eplfs,moveonenospc=true,minfreespace=20G,fsname=mergerfsPool 0 0This will create /storage concatenated from all disks mounted under /datadf -h now showsmergerfsPool 26T 617M 26T 1% /storageNice!ssh serverrsync --partial --progress --inplace --whole-file -av -e ssh /data/movies/* 10.11.12.116:/storage/movies/My staging area is not big enough to hold my whole server. But it will fit /data/movies just fine. So we will start out with that.Firstps -ef |grep unionfs too see the command originally used to mount unionfs with. NB! This will differ from system to system depending on your pgmove/pgblitz setup. So take a note of the one used on your system. Don't copy this one directly.thenumount /mnt/unionfsThenumount /storageThen change /storage mountpoint in fstab to be /mnt/movethenmount /mount/movethenmount unionfs using the command you to note of with ps -ef when we started./usr/bin/unionfs -o cow,allow_other,nonempty,direct_io,auto_cache,sync_read /mnt/move=RW:/mnt/gdrive=RO:/mnt/tdrive=RO:/mnt/gcrypt=RO:/mnt/tcrypt=RO:/mnt/pgblitz/gdsa01=RO:/mnt/pgblitz/gdsa02=RO:/mnt/pgblitz/gdsa03=RO:/mnt/pgblitz/gdsa04=RO:/mnt/pgblitz/gdsa05=RO:/mnt/pgblitz/gdsa06=RO:/mnt/pgblitz/gdsa07=RO:/mnt/pgblitz/gdsa08=RO: /mnt/unionfsIt should start uploading data nowcheck withpglogWhen /mnt/move is empty and we are ready to migrate the next directory to stage, we need to reset mount points to make the staging server ready to recieve from original/old plex server again.umount /mnt/unionfsumount /mnt/moveedit vfstabvi /etc/fstabThen change mergerfs /mnt/move mount point in fstab back to being /storagemount /storagethen mount /mnt/unionfs using the command you found with ps -ef/mnt/move=RW:/mnt/gdrive=RO:/mnt/tdrive=RO:/mnt/gcrypt=RO:/mnt/tcrypt=RO:/mnt/pgblitz/gdsa01=RO:/mnt/pgblitz/gdsa02=RO:/mnt/pgblitz/gdsa03=RO:/mnt/pgblitz/gdsa04=RO:/mnt/pgblitz/gdsa05=RO:/mnt/pgblitz/gdsa06=RO:/mnt/pgblitz/gdsa07=RO:/mnt/pgblitz/gdsa08=RO: /mnt/unionfsGo to NB! -- this section repeats -- and migrate your next directory or however much you can fit on your stage disk/disks.At this point you can umount /storage and all the /data/disk[1-x]remove them from /etc/fstabshut down the server and remove the staging disks.