zfs-snapshot

The following script allows you to create ZFS snapshots of EOS blocks/ and state/ folders. Please note this is not for block producers, as you need to stop your nodeos process.

TO-DO

Remove old snapshots once per day - set daily cron to remove snapshots and create new one and then let hourly take over.

Requirements

• Working ZFS install
• ZFS volume
• When starting nodeos you should point your data-dir to your ZFS volume.

Installation

Step 1 - Reconfigure your Nodeos startup script.

• We need to modify your startup scripts to point our --data-dir to our ZFS volumes.
• My volume is called eos.

#!/bin/bash
################################################################################
#
# Scrip Created by http://CryptoLions.io
# For EOS Junlge testnet
#
# https://github.com/CryptoLions/
#
################################################################################
NODEOS=/opt/eos/build2/programs/nodeos/nodeos
DATADIR=/opt/JungleTestnet-panthereos42
ZFS=/eos
$DATADIR/stop.sh
$NODEOS --data-dir $ZFS --config-dir $DATADIR "$@" > $DATADIR/stdout.txt 2> $DATADIR/stderr.txt &  echo $! > $DATADIR/nodeos.pid

Step 2 - Install zfs-backup script.

• Download and place the zfs-backup.sh in a folder of your choice.
• Give executable permissions Chmod +x /opt/scripts/zfs-backup.sh

Step 3 - Create Cronfile to run hourly at minute 5.

• Add the following to your /etc/cron.d.
• replace %username% what you use to start and stop nodeos
• 5 * * * * root sudo -u charles "/opt/scripts/zfs-backup.sh"

Addtional information.

• The reasoning behind sudo -u %username% is because we want nodeos to start with a non root user, but we need ZFS to run as root.

Setup cron script to remove all but the last ZFS snapshot

zfs list -t snapshot -o name | grep ^eos@ | tac | tail -n +16 | xargs -n 1 zfs destroy -r

• output the list of snapshot (names only) with zfs list -t snaphot -o name
• filter to keep only the ones that match tank@Auto with grep ^eos@
• reverse the list (previously sorted from oldest to newest) with tac
• limit output to the 16th oldest result and following with tail -n +16
• then destroy with xargs -n 1 zfs destroy -vr

Revert back to a snapshot

Step 1 - Stop your nodeos process & delete current blocks and state

Step 2 - List and revert back to latest snapshot

sudo zfs list -t snapshot  
NAME                   USED  AVAIL  REFER  MOUNTPOINT
eos@2018_10_04-19_24  1.02G      -  56.4G  -
eos@2018_10_04-19_43   967M      -  56.4G  -
eos@2018_10_04-19_59   970M      -  56.4G  -

sudo zfs rollback -r eos@2018_10_04-19_59

Step 3 - Restart nodeos process.