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--- zfs_root_cache [2020/11/25 06:28] – memeruiz
+++ zfs_root_cache [2021/02/01 05:55] (current) – external edit 127.0.0.1
@@ Line 124: / Line 124: @@
   LABEL=tardis   		      	    		/swap	      btrfs defaults,noatime,subvol=swap	0 0
   UUID="11d65735-75d0-44ce-a158-abd01d98b318"	/boot	      ext4  defaults,noatime			0 0
+===== New system =====
+  * Reboot to new system
+==== Create a ZFS pool for main big data! ====
+  * option 1: Stripping
+  sudo zpool create tardis  /dev/sdb4 /dev/sde4 /dev/sdf4
+  * option 2: raidz1 (with 3 new disks in raidz1 configuration of 2xdisk space)
+  sudo zpool create tardis raidz1 /dev/sdb4 /dev/sde4 /dev/sdf4
+  * option 3: raidz1 but degraded. (without one disk at the beginning) Solution: Use a sparse file as one of the starting disks [10].
+  truncate -s 8T tardisfake.img (Use the same exact size of the real disk partition)
+  sudo zpool create tardis raidz1 /dev/sde4 /dev/sdf4 /home/memeruiz/tardisfake.img
+  sudo zpool offline tardisnew /home/memeruiz/tardisfake.img
+  * Add log and cache devices:
+  sudo zpool add tardis log /dev/nvme0n1p1
+  sudo zpool add tardis cache /dev/nvme0n1p2
+  * Create encrypted volume
+  sudo zfs create -o encryption=on -o keyformat=passphrase tardis/data
+  * Create compressed subvolume
+  sudo zfs create tardis/data/compressed
+  sudo zfs set compression=on tardis/data/compressed
+  * Avoid data to be mounted automatically with zfs:
+  sudo zfs set mountpoint=legacy tardis/data
+==== How to mount encrypted volume ====
+  * If pool was already activated, deactivate it!
+  sudo zpool export tardis
+  * Reactivate pool with -l option to ask for decryption passphrase:
+  sudo zpool import tardis -l
+  * Mount fs:
+  sudo mount -t zfs tardis/data /srv
+  * Extending a pool:
+  zpool add tardis /dev/<diskfile>
@@ Line 148: / Line 206: @@
   zpool remove poolname device
+==== If a pool becomes damaged or some: Permanent error in some files  ====
+  errors: Permanent errors have been detected in the following files:
+You can fix that be doing a short scrubing and then stopping:
+  sudo zpool scrub tardis
+  # wait a bit
+  sudo zpool scrub -s tardis
+Then error messages are gone
+==== In case you want to interchange (replace) a pool disk (no redundancy). ====
+For example: if this disk is getting damaged: you may want to replace it with a new one, some files may be broken, but using:
+  sudo zpool replace tardis old_dev new_dev
+This will copy everthing from the zfs from that disk to the new one, attach the new one and detach the old one. In this way, it is not necessary to copy the whole disk with dd.
+==== Create a zfs pool using files instead of real disks ====
+  mkfile 100m file1
+  zpool create geekpool /file1
+==== Create a ZFS raidz1 en degrated mode ====
+  * Create a sparse file with the same size of your harddrives. Then remove it before putting files to it.
+[[https://www.reddit.com/r/zfs/comments/8enkt8/can_i_create_a_new_raidz_in_degraded_mode/]]
@@ Line 167: / Line 259: @@
 [[https://openzfs.github.io/openzfs-docs/Getting%20Started/Debian/Debian%20Buster%20Root%20on%20ZFS.html]]
+[[https://mohankumar-k.blogspot.com/2018/05/how-to-resolve-zpool-permanent-errors.html]]
+[[https://docs.oracle.com/cd/E36784_01/html/E36835/gbbvf.html]]
+[[https://www.thegeekdiary.com/zfs-tutorials-creating-zfs-pools-and-file-systems/]]
+[[https://www.delphix.com/blog/delphix-engineering/openzfs-code-walk-metaslabs-and-space-maps]]
+[10] [[https://www.mail-archive.com/zfs-discuss@opensolaris.org/msg22993.html]]
+[[https://unix.stackexchange.com/questions/322352/create-raid-z2-in-degraded-state-possible]]