ChrisYx511

I've modified @Tomr's snapshot with retention policy script to merge in @catapultam_habeo's original snapshot pruning method in order to improve the reliability of snapsot pruning. I've changed it back to a number of snapshots being retained instead of retention minutes. I found that going off minutes was fairly unreliable and often failed to auto-prune. EDIT: Forgot I also added back the exclusion list instead of an inclusion list. Instructions for shadow copy remains unchanged: Here's the script: #!/bin/bash #description=This script implements incremental snapshots on btrfs array drives. #arrayStarted=true ## Credits # catapultam_habeo - Initial script # Tomr - Modified version with SNAPSHOT_TYPE retention policy #If you change the type you'll have to delete the old snapshots manually #valid values are: hourly, daily, weekly, monthly SNAPSHOT_TYPE=hourly #How many snapshots should be kept. MAX_SNAPS= #Name of the shares to exclude, can be comma separated like "medias,valuables" EXCLUDE= #name of the snapshot folder and delimeter. Do not change. #https://www.samba.org/samba/docs/current/man-html/vfs_shadow_copy2.8.html SNAPSHOT_DELIMETER="_UTC_" SNAPSHOT_FORMAT="$(TZ=UTC date +${SNAPSHOT_TYPE}${SNAPSHOT_DELIMETER}%Y.%m.%d-%H.%M.%S)" shopt -s nullglob #make empty directories not freak out is_btrfs_subvolume() { local dir=$1 [ "$(stat -f --format="%T" "$dir")" == "btrfs" ] || return 1 inode="$(stat --format="%i" "$dir")" case "$inode" in 2|256) return 0;; *) return 1;; esac } #ADJUST MAX_SNAPS to prevent off-by-1 MAX_SNAPS=$((MAX_SNAPS+1)) #Tokenize exclude list declare -A excludes for token in ${EXCLUDE//,/ }; do excludes[$token]=1 done #iterate over all disks on array for disk in /mnt/disk*[0-9]* ; do #examine disk for btrfs-formatting (MOSTLY UNTESTED) if is_btrfs_subvolume $disk ; then #iterate over shares present on disk for share in ${disk}/* ; do declare baseShare=$(basename $share) #test for exclusion if [ -n "${excludes[$baseShare]}" ]; then echo "$share is on the exclusion list. Skipping..." else #check for .snapshots directory prior to generating snapshot #only before we make the actual snapshot #so we don't create empty folders if [ -d "$disk" ]; then if [ ! -d "$disk/.snapshots/$SNAPSHOT_FORMAT/" ] ; then #echo "new" mkdir -v -p $disk/.snapshots/$SNAPSHOT_FORMAT fi fi #echo "Examining $share on $disk" is_btrfs_subvolume $share if [ ! "$?" -eq 0 ]; then echo "$share is likely not a subvolume" mv -v ${share} ${share}_TEMP btrfs subvolume create $share cp -avT --reflink=always ${share}_TEMP $share rm -vrf ${share}_TEMP fi #make new snap btrfs subvolume snap -r ${share} $disk/.snapshots/${SNAPSHOT_FORMAT}/$baseShare fi done #find old snaps echo "Found $(find ${disk}/.snapshots/${SNAPSHOT_TYPE}${SNAPSHOT_DELIMETER}*/ -maxdepth 0 -mindepth 0 | sort -nr | tail -n +$MAX_SNAPS | wc -l) old snaps" for snap in $(find ${disk}/.snapshots/${SNAPSHOT_TYPE}${SNAPSHOT_DELIMETER}*/ -maxdepth 0 -mindepth 0 | sort -nr | tail -n +$MAX_SNAPS); do for share_snap in ${snap}/*; do btrfs subvolume delete $share_snap done rmdir $snap --ignore-fail-on-non-empty done fi done Hope it's useful!