====== Linux ZFS ======
https://lepkov.ru/zfs-cheatsheet/ backup https://habr.com/ru/companies/macloud/articles/547056/ \\
<https://denisbondar.github.io/post/zfs-manual-rus/> - manual <https://xakep.ru/2014/07/08/zfs-at-home/#toc07.> old one\\
<code BASH>
# zfs pools and mount points
tree /dev/zvol/
/dev/zvol/
├── rpool
    ├── data
    │   ├── vm-100-disk-1 -> ../../../zd0
    │   └── vm-100-disk-1-part1 -> ../../../zd0p1
    └── swap -> ../../zd16
    
zfs get all rpool/data/subvol-111-disk-1  | grep com
zfs set compression=off rpool/data/subvol-111-disk-1
    
zfs get compressratio
NAME                          PROPERTY       VALUE  SOURCE
rpool                         compressratio  1.07x  -
rpool/ROOT                    compressratio  1.78x  -
rpool/ROOT/pve-1              compressratio  1.78x  -
rpool/data                    compressratio  1.06x  -
rpool/data/subvol-110-disk-0  compressratio  1.77x  -


# start trim operation
 zpool trim rpool
# show status
 zpool status -t rpool
</code>

===== ZFS move - recompress =====
++++ Recompress zfs|
<code BASH>
#You basically have to rewrite every block of every file.

#A reasonably safe and simple way to do it is like this, however this
#assumes you have sufficient space.

#First set the new value for compression.

zfs set compression=on tank/fs

#Send a snapshot to a temporary name

zfs snapshot tank/***@1
zfs send -R tank/***@1 | zfs recv -vFd tank/fs-recompressed

#Mark the original as readonly and send anything newly written
#since the 'zfs send' above started.

zfs set readonly=on tank/fs
zfs snapshot tank/***@2
zfs send -i tank/***@1 tank/***@2 | zfs recv -v tank/fs-recompressed

#Now delete the original and rename the newone into its place.

zfs delete tank/fs
zfs rename tank/fs-recompressed tank/fs

#Note that the new tank/fs will have all the the snapshots of
#the original as well since -R was used with the zfs send.
</code>
++++


===== ZFS - notification =====
++++ telegram notification zfs|
<code BASH>
 # https://github.com/leovp/telegram_notifications
nano /etc/zfs/zed.d/zed-telegram.sh

#!/bin/bash
TELEGRAM_BOT_TOKEN="righttoken" # put your token here
TELEGRAM_CHAT_ID="chatid" # your chat_id for sending notification

subject="$1"
details="$2"

MESSAGE="🚨 ZFS Alert on $(hostname) 🚨
Event: $subject
Details:
$details"

curl -s -X POST "https://api.telegram.org/bot$TELEGRAM_BOT_TOKEN/sendMessage" \
     -d "chat_id=$TELEGRAM_CHAT_ID" \
     -d "text=$MESSAGE"

chmod +x /etc/zfs/zed.d/zed-telegram.sh

# zed-functions.sh Modified zed_notify function
zed_notify()
{
    zed_notify_email "${subject}" "${pathname}"; rv=$?
    [ "${rv}" -eq 0 ] && num_success=$((num_success + 1))
    [ "${rv}" -eq 1 ] && num_failure=$((num_failure + 1))

    # Execute external Telegram script if it exists
    if [ -x "/etc/zfs/zed.d/zed-telegram.sh" ]; then
        /etc/zfs/zed.d/zed-telegram.sh "${subject}" "$(cat "${pathname}")"; rv=$?
        [ "${rv}" -eq 0 ] && num_success=$((num_success + 1))
        [ "${rv}" -eq 1 ] && num_failure=$((num_failure + 1))
    fi
}
</code>
++++




===== ZFS backup =====

<code bash>
# create file  20 gb
dd if=/dev/zero of=/mnt/sdb3/zpool_test bs=1G count=20
# create pool on file 
zpool create test /mnt/sdb3/zpool_test


# send data replication to local  system 
 zfs send -vR rpool@snap1 | zfs receive  test -F

# send data of zpool to file 
zfs send -vR rpool@snap1 > /mnt/pve/backup/zfs-pve-rpool-20240624.backup
# recieve 
zfs receive rpool < /mnt/pve/backup/zfs-pve-rpool-20240624.backup


zpool attach rpool nvme-512GB_SSD_NJM358R015419P70GX-part3 ata-SPCC_Solid_State_Disk_AA230918S351201018-part3
zpool remove rpool /mnt/sdb3/zpool_mirror1_1
</code>

===== ZFS monitoring =====
https://blog.roberthallam.org/2022/09/monitoring-zfs-with-influxdb-grafana-publishing-and-reflection-part-5/ \\
https://github.com/richardelling/zpool_influxdb \\