First zfs scripts

2026-06-02 14:56:58 +02:00 · 2026-04-18 00:30:13 +02:00
parent 72bbf86921
commit 74f381cc1c
3 changed files with 441 additions and 0 deletions
@@ -0,0 +1,122 @@
+#!/bin/bash
+
+function printFoundCommonSnapshot() {
+    local _ZFS _COMMON_SNAPSHOT_CANDIDATE
+    _ZFS="${1:?"printFoundCommonSnapshot(): Missing first parameter ZFS"}"
+    _COMMON_SNAPSHOT_CANDIDATE="${2:?"printFoundCommonSnapshot(): Missing second parameter COMMON_SNAPSHOT_CANDIDATE"}"
+    readonly _ZFS _COMMON_SNAPSHOT_CANDIDATE
+
+    local _FOUND_COMMON_SNAPSHOT
+    _FOUND_COMMON_SNAPSHOT=""
+
+    while read -r _ROW
+    do
+        if [ "${_ROW}" == "${_ZFS}@${_COMMON_SNAPSHOT_CANDIDATE}" ]; then
+            _FOUND_COMMON_SNAPSHOT="${_ROW}"
+            break
+        fi
+    done < <(zfs list -H -o name -S creation -t snapshot "${_ZFS}")
+
+    [ $? -eq 0 ] \
+        && echo "${_FOUND_COMMON_SNAPSHOT}" \
+        && return 0
+
+    return 1
+}
+
+function removeAllSyncSnapshotsExeptTheCommonOne() {
+    local _ZFS _RECEIVERHOST _COMMON_SNAPSHOT
+    _ZFS="${1:?"removeAllSyncSnapshotsExeptTheCommonOne(): Missing first parameter ZFS"}"
+    _RECEIVERHOST="${2:?"removeAllSyncSnapshotsExeptTheCommonOne(): Missing second parameter RECEIVERHOST"}"
+    _COMMON_SNAPSHOT="${3:?"removeAllSyncSnapshotsExeptTheCommonOne(): Missing third parameter COMMON_SNAPSHOT"}"
+    readonly _ZFS _RECEIVERHOST _COMMON_SNAPSHOT
+
+    while read -r _ROW
+    do
+        # Skip the common snapshot to keep it.
+        # If the common snapshot is not a sync-snapshot all sync-snapshots will be removed.
+        if [ "${_ROW}" == "${_COMMON_SNAPSHOT}" ]; then
+            continue
+        fi
+        # Destroy all remaining sync-snapshots of the receiving host
+        zfs destroy "${_ROW}"
+    done < <(zfs list -H -o name -S creation -t snapshot "${_ZFS}" | grep -E "^${_ZFS}@SYNC_${_RECEIVERHOST}_")
+}
+
+function sendResume() {
+    local _RESUME_TOKEN
+    _RESUME_TOKEN="${1:?"sendResume(): Missing first parameter RESUME_TOKEN"}"
+    readonly _RESUME_TOKEN
+
+    zfs send -t "${RESUME_TOKEN}" \
+        && return 0
+
+    return 1
+}
+
+function isValid() {
+    # printf '%s'
+    #  - always treats the contents of ${1} as pure plain text.
+    # grep -qE: checks RegExp, but quiet
+    printf '%s' "${1}" | grep -qE "${2:?"isValid(): Missing REGEXP"}"
+}
+
+function isValidOptional() {
+    [ -z "${1}" ] || isValid "${1}" "${2}"
+}
+
+
+
+# Parameter 1: Only alphanumeric characters allowed and [._-]  if not leading (due to: -oProxyCommand=...).
+# Parameter 2: Only alphanumeric characters allowed and [.-]   if not leading (due to: -oProxyCommand=...).
+# Parameter 3: Only alphanumeric characters allowed and [._:-] if not leading (due to: -oProxyCommand=...), but can be empty.
+# Parameter 4: Only alphanumeric characters allowed and [._:-] if not leading (due to: -oProxyCommand=...), but can be empty.
+if isValid "${1:?"RECEIVERHOST missing"}" '^[a-zA-Z0-9][a-zA-Z0-9._-]*$' \
+    && isValid "${2:?"COMPOSITION missing"}" '^[a-zA-Z0-9][a-zA-Z0-9.-]*$' \
+    && isValidOptional "${3}" '^[a-zA-Z0-9][a-zA-Z0-9._:-]*$' \
+    && isValidOptional "${4}" '^[a-zA-Z0-9][a-zA-Z0-9._:-]*$'
+then
+    _RECEIVERHOST="${1}"
+    _COMPOSITION="${2}"
+    _RECEIVERS_SNAPSHOT="${3}"
+    _RESUME_TOKEN="${4}"
+
+    _ZFS="zpool1/persistent/${_COMPOSITION:?"COMPOSITION missing"}"
+
+    # Resume mode
+    if [ "${_RECEIVERS_SNAPSHOT}" == "RESUME" ]; then
+        sendResume "${_RESUME_TOKEN}"
+        exit $?
+    fi
+
+    # This common snapshot is the starting-point, if available.
+    _COMMON_SNAPSHOT="$(printFoundCommonSnapshot ${_ZFS} ${_RECEIVERS_SNAPSHOT})"
+
+    [ "${_COMMON_SNAPSHOT}" == "" ] \
+        && [ "${_RECEIVERS_SNAPSHOT}" != "" ] \
+        && echo "Requested snapshot '${_RECEIVERS_SNAPSHOT}' not available" \
+        && exit 1
+
+    [ "${_COMMON_SNAPSHOT}" != "" ] \
+        && removeAllSyncSnapshotsExeptTheCommonOne "${_ZFS}" "${_RECEIVERHOST}" "${_COMMON_SNAPSHOT}"
+
+    # Now create the first or a further sync-snapshot as end-point.
+    _NEW_SNAPSHOT="${_ZFS}@SYNC_${_RECEIVERHOST:?"RECEIVERHOST missing"}_$(date -u "+%Y-%m-%d_%H:%M:%S")"
+
+    [ "${_COMMON_SNAPSHOT}" == "" ] \
+        && zfs snapshot "${_NEW_SNAPSHOT}" \
+        && zfs send -c -R "${_NEW_SNAPSHOT}" \
+        && exit 0
+
+    [ "${_COMMON_SNAPSHOT}" != "" ] \
+        && removeAllSyncSnapshotsExeptTheCommonOne "${_ZFS}" "${_RECEIVERHOST}" "${_COMMON_SNAPSHOT}" \
+        && zfs snapshot "${_NEW_SNAPSHOT}" \
+        && zfs send -c -R -I "${_COMMON_SNAPSHOT}" "${_NEW_SNAPSHOT}" \
+        && exit 0
+
+else
+    echo "Failure: At least one parameter is invalid" >&2
+    exit 1
+fi
+
+exit 1