添加 incremental_backup.sh
This commit is contained in:
564
incremental_backup.sh
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564
incremental_backup.sh
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#!/bin/bash
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# ============================================================================
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# MySQL 8.0.24 增量备份脚本
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# ============================================================================
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# 作者: AI Assistant
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# 版本: 1.0.0
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# 说明: 基于 binlog 的增量备份
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#
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# 功能特点:
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# - 基于 binlog 实现增量备份
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# - 从上次全量/增量备份点开始备份
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# - 支持压缩
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# - 自动清理过期备份
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#
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# 工作原理:
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# 1. 读取上次备份记录的 binlog 位置
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# 2. 复制从该位置到当前位置的 binlog 文件
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# 3. 记录新的 binlog 位置用于下次增量备份
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#
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# 使用方法:
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# ./incremental_backup.sh [选项]
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#
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# 选项:
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# -f, --full-backup <path> 指定全量备份目录 (默认使用最新的全量备份)
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# -c, --compress 启用压缩 (默认: 是)
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# -n, --no-compress 禁用压缩
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# -h, --help 显示帮助信息
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#
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# 前提条件:
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# - 必须先执行过全量备份
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# - MySQL 必须启用 binlog
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# - MySQL 用户需要 REPLICATION SLAVE, REPLICATION CLIENT 权限
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# ============================================================================
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set -o pipefail
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# ----------------------------------------------------------------------------
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# 脚本路径和配置加载
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# ----------------------------------------------------------------------------
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SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
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# 加载配置文件
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if [[ ! -f "${SCRIPT_DIR}/config.sh" ]]; then
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echo "[ERROR] 配置文件不存在: ${SCRIPT_DIR}/config.sh"
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exit 1
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fi
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source "${SCRIPT_DIR}/config.sh"
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# 加载公共函数库
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if [[ ! -f "${SCRIPT_DIR}/lib/common.sh" ]]; then
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echo "[ERROR] 公共函数库不存在: ${SCRIPT_DIR}/lib/common.sh"
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exit 1
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fi
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source "${SCRIPT_DIR}/lib/common.sh"
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# ----------------------------------------------------------------------------
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# 全局变量
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# ----------------------------------------------------------------------------
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BACKUP_TIMESTAMP=$(date +"${TIMESTAMP_FORMAT}")
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BACKUP_NAME="${BACKUP_PREFIX}_incr_${BACKUP_TIMESTAMP}"
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BACKUP_DIR="${INCREMENTAL_BACKUP_DIR}/${BACKUP_NAME}"
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LOCK_FILE="${BACKUP_ROOT_DIR}/.incremental_backup.lock"
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LOG_FILE="${LOG_DIR}/incremental_backup_${BACKUP_TIMESTAMP}.log"
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ENABLE_COMPRESS=true
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SPECIFIED_FULL_BACKUP=""
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BASE_BACKUP_DIR="" # 基准备份目录 (全量或上次增量)
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# ----------------------------------------------------------------------------
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# 显示帮助信息
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# ----------------------------------------------------------------------------
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show_help() {
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cat << EOF
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MySQL 8.0.24 增量备份脚本
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使用方法:
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$(basename "$0") [选项]
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选项:
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-f, --full-backup <path> 指定全量备份基准目录
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-b, --base-backup <path> 指定增量备份基准目录 (用于增量链)
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-c, --compress 启用压缩 (默认: 是)
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-n, --no-compress 禁用压缩
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-h, --help 显示此帮助信息
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示例:
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$(basename "$0") # 基于最新全量备份
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$(basename "$0") -f /path/to/full_backup # 指定全量备份
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$(basename "$0") -b /path/to/last_incr_backup # 基于上次增量备份
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说明:
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增量备份基于 MySQL binlog 实现。脚本会从基准备份记录的 binlog
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位置开始，复制到当前 binlog 位置的所有日志。
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前提条件:
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- 必须先执行过全量备份
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- MySQL 必须启用 binlog (log_bin=ON)
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- MySQL 用户需要 REPLICATION SLAVE, REPLICATION CLIENT 权限
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EOF
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}
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# ----------------------------------------------------------------------------
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# 解析命令行参数
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# ----------------------------------------------------------------------------
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parse_args() {
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while [[ $# -gt 0 ]]; do
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case "$1" in
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-f|--full-backup)
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shift
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if [[ -z "$1" ]]; then
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die "选项 -f/--full-backup 需要一个参数"
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fi
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SPECIFIED_FULL_BACKUP="$1"
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shift
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;;
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-b|--base-backup)
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shift
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if [[ -z "$1" ]]; then
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die "选项 -b/--base-backup 需要一个参数"
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fi
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BASE_BACKUP_DIR="$1"
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shift
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;;
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-c|--compress)
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ENABLE_COMPRESS=true
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shift
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;;
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-n|--no-compress)
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ENABLE_COMPRESS=false
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shift
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;;
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-h|--help)
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show_help
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exit 0
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;;
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*)
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die "未知选项: $1\n使用 --help 查看帮助"
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;;
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esac
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done
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}
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# ----------------------------------------------------------------------------
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# 检查 binlog 是否启用
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# ----------------------------------------------------------------------------
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check_binlog_enabled() {
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log_info "检查 binlog 状态..."
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local binlog_status=$(execute_mysql "SHOW VARIABLES LIKE 'log_bin';")
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if ! echo "$binlog_status" | grep -q "ON"; then
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die "MySQL binlog 未启用。请在 my.cnf 中设置 log_bin=ON"
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fi
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log_info "Binlog 已启用"
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}
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# ----------------------------------------------------------------------------
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# 获取 binlog 目录
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# ----------------------------------------------------------------------------
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get_binlog_dir() {
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local binlog_basename=$(execute_mysql "SHOW VARIABLES LIKE 'log_bin_basename';" | awk '{print $2}')
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if [[ -z "$binlog_basename" ]]; then
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# 尝试使用数据目录
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echo "$MYSQL_DATA_DIR"
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else
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dirname "$binlog_basename"
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fi
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}
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# ----------------------------------------------------------------------------
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# 查找基准备份
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# ----------------------------------------------------------------------------
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find_base_backup() {
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if [[ -n "$BASE_BACKUP_DIR" ]]; then
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# 使用指定的基准备份
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if [[ ! -d "$BASE_BACKUP_DIR" ]]; then
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die "指定的基准备份目录不存在: $BASE_BACKUP_DIR"
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fi
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echo "$BASE_BACKUP_DIR"
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return
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fi
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if [[ -n "$SPECIFIED_FULL_BACKUP" ]]; then
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# 使用指定的全量备份
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if [[ ! -d "$SPECIFIED_FULL_BACKUP" ]]; then
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die "指定的全量备份目录不存在: $SPECIFIED_FULL_BACKUP"
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fi
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echo "$SPECIFIED_FULL_BACKUP"
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return
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fi
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# 首先查找最新的增量备份
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local latest_incr=$(find "$INCREMENTAL_BACKUP_DIR" -maxdepth 1 -type d -name "${BACKUP_PREFIX}_incr_*" 2>/dev/null | sort -r | head -n1)
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if [[ -n "$latest_incr" && -f "${latest_incr}/binlog_position.txt" ]]; then
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log_info "找到最新的增量备份作为基准: $latest_incr"
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echo "$latest_incr"
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return
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fi
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# 查找最新的全量备份
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local latest_full=$(find "$FULL_BACKUP_DIR" -maxdepth 1 -type d -name "${BACKUP_PREFIX}_full_*" 2>/dev/null | sort -r | head -n1)
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if [[ -z "$latest_full" ]]; then
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die "没有找到可用的全量备份。请先执行全量备份"
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fi
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if [[ ! -f "${latest_full}/binlog_position.txt" ]]; then
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die "全量备份缺少 binlog 位置信息: $latest_full"
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fi
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log_info "使用全量备份作为基准: $latest_full"
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echo "$latest_full"
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}
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# ----------------------------------------------------------------------------
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# 读取基准 binlog 位置
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# ----------------------------------------------------------------------------
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read_base_binlog_position() {
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local base_dir="$1"
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local position_file="${base_dir}/binlog_position.txt"
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if [[ ! -f "$position_file" ]]; then
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die "找不到 binlog 位置文件: $position_file"
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fi
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source "$position_file"
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if [[ -z "$BINLOG_FILE" || -z "$BINLOG_POSITION" ]]; then
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die "binlog 位置信息不完整"
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fi
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echo "${BINLOG_FILE}:${BINLOG_POSITION}"
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}
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# ----------------------------------------------------------------------------
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# 获取 binlog 文件列表
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# ----------------------------------------------------------------------------
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get_binlog_files_to_backup() {
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local start_file="$1"
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local start_pos="$2"
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local binlog_dir="$3"
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# 获取当前 binlog 位置
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local current_pos=$(get_binlog_position)
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local current_file=$(echo "$current_pos" | cut -d: -f1)
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local current_position=$(echo "$current_pos" | cut -d: -f2)
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log_info "起始 binlog: $start_file:$start_pos"
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log_info "当前 binlog: $current_file:$current_position"
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# 获取 binlog 索引文件
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local binlog_index=$(execute_mysql "SHOW VARIABLES LIKE 'log_bin_index';" | awk '{print $2}')
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# 获取需要备份的文件列表
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local in_range=false
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local files_to_backup=()
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# 使用 SHOW BINARY LOGS 获取文件列表
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local log_list=$(execute_mysql "SHOW BINARY LOGS;" | awk '{print $1}')
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while IFS= read -r log_file; do
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if [[ "$log_file" == "$start_file" ]]; then
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in_range=true
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fi
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if [[ "$in_range" == true ]]; then
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files_to_backup+=("$log_file")
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fi
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if [[ "$log_file" == "$current_file" ]]; then
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break
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fi
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done <<< "$log_list"
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echo "${files_to_backup[@]}"
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}
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# ----------------------------------------------------------------------------
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# 初始化备份环境
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# ----------------------------------------------------------------------------
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init_backup() {
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log_info "============================================================"
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log_info "MySQL 增量备份开始"
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log_info "============================================================"
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log_info "备份时间: $BACKUP_TIMESTAMP"
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log_info "备份目录: $BACKUP_DIR"
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log_info "日志文件: $LOG_FILE"
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log_info "============================================================"
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# 设置错误处理
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setup_error_trap
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# 检查必要命令
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check_commands "$MYSQL_PATH" "$MYSQLBINLOG_PATH" "gzip"
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# 检查 MySQL 连接
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check_mysql_connection
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# 检查 binlog 是否启用
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check_binlog_enabled
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# 创建必要目录
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ensure_dir "$BACKUP_DIR"
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ensure_dir "$LOG_DIR"
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# 检查磁盘空间
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check_disk_space "$BACKUP_DIR" 2048
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# 获取锁
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acquire_lock "$LOCK_FILE" "增量备份"
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# 设置清理 trap
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trap cleanup EXIT
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}
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# ----------------------------------------------------------------------------
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# 清理函数
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# ----------------------------------------------------------------------------
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cleanup() {
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local exit_code=$?
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# 释放锁
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release_lock "$LOCK_FILE"
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if [[ $exit_code -ne 0 ]]; then
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log_error "备份过程中发生错误，退出码: $exit_code"
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# 清理不完整的备份
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if [[ -d "$BACKUP_DIR" ]]; then
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log_warn "清理不完整的备份目录: $BACKUP_DIR"
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rm -rf "$BACKUP_DIR"
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fi
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send_notification "[失败] MySQL 增量备份" "备份失败，请检查日志: $LOG_FILE"
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fi
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}
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# ----------------------------------------------------------------------------
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# 执行 binlog 备份
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# ----------------------------------------------------------------------------
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backup_binlogs() {
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local base_dir="$1"
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local binlog_dir=$(get_binlog_dir)
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log_info "Binlog 目录: $binlog_dir"
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# 读取基准位置
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local base_pos=$(read_base_binlog_position "$base_dir")
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local start_file=$(echo "$base_pos" | cut -d: -f1)
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local start_position=$(echo "$base_pos" | cut -d: -f2)
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# 获取当前位置
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local current_pos=$(get_binlog_position)
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local end_file=$(echo "$current_pos" | cut -d: -f1)
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local end_position=$(echo "$current_pos" | cut -d: -f2)
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# 检查是否有新的数据需要备份
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if [[ "$start_file" == "$end_file" && "$start_position" == "$end_position" ]]; then
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log_warn "没有新的 binlog 数据需要备份"
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log_warn "起始位置和当前位置相同: $start_file:$start_position"
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# 创建空的增量备份记录
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save_binlog_position "$end_file" "$end_position"
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return 0
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fi
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# 获取需要备份的 binlog 文件列表
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local files=$(get_binlog_files_to_backup "$start_file" "$start_position" "$binlog_dir")
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if [[ -z "$files" ]]; then
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log_warn "没有需要备份的 binlog 文件"
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save_binlog_position "$end_file" "$end_position"
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return 0
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fi
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log_info "需要备份的 binlog 文件: $files"
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local backup_count=0
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local is_first_file=true
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for binlog_file in $files; do
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log_info "备份 binlog: $binlog_file"
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local binlog_path="${binlog_dir}/${binlog_file}"
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local output_file="${BACKUP_DIR}/${binlog_file}"
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if [[ ! -f "$binlog_path" ]]; then
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# binlog 可能已被清理，尝试从 MySQL 读取
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log_warn "本地 binlog 文件不存在，尝试使用 mysqlbinlog 远程读取"
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local mysqlbinlog_args="-h${MYSQL_HOST} -P${MYSQL_PORT} -u${MYSQL_USER}"
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if [[ -n "$MYSQL_PASSWORD" ]]; then
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mysqlbinlog_args="$mysqlbinlog_args -p${MYSQL_PASSWORD}"
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fi
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# 对于第一个文件，从指定位置开始
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if [[ "$is_first_file" == true && "$binlog_file" == "$start_file" ]]; then
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mysqlbinlog_args="$mysqlbinlog_args --start-position=$start_position"
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fi
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# 对于最后一个文件，在指定位置停止
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if [[ "$binlog_file" == "$end_file" ]]; then
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mysqlbinlog_args="$mysqlbinlog_args --stop-position=$end_position"
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fi
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mysqlbinlog_args="$mysqlbinlog_args --read-from-remote-server"
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if ! $MYSQLBINLOG_PATH $mysqlbinlog_args "$binlog_file" > "$output_file" 2>> "$LOG_FILE"; then
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die "备份 binlog 失败: $binlog_file"
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fi
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else
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# 使用本地 binlog 文件
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local mysqlbinlog_args=""
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# 对于第一个文件，从指定位置开始
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if [[ "$is_first_file" == true && "$binlog_file" == "$start_file" ]]; then
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mysqlbinlog_args="--start-position=$start_position"
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fi
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# 对于最后一个文件，在指定位置停止
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if [[ "$binlog_file" == "$end_file" ]]; then
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mysqlbinlog_args="$mysqlbinlog_args --stop-position=$end_position"
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fi
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if ! $MYSQLBINLOG_PATH $mysqlbinlog_args "$binlog_path" > "$output_file" 2>> "$LOG_FILE"; then
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die "备份 binlog 失败: $binlog_file"
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fi
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fi
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# 压缩
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if [[ "$ENABLE_COMPRESS" == "true" ]]; then
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gzip -f "$output_file" || die "压缩失败: $output_file"
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output_file="${output_file}.gz"
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fi
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((backup_count++))
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is_first_file=false
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log_info "备份完成: $(get_file_size $output_file)"
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done
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||||
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||||
log_info "共备份 $backup_count 个 binlog 文件"
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||||
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||||
# 记录新的 binlog 位置
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||||
save_binlog_position "$end_file" "$end_position"
|
||||
}
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||||
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||||
# ----------------------------------------------------------------------------
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||||
# 保存 binlog 位置
|
||||
# ----------------------------------------------------------------------------
|
||||
save_binlog_position() {
|
||||
local binlog_file="$1"
|
||||
local binlog_pos="$2"
|
||||
local position_file="${BACKUP_DIR}/binlog_position.txt"
|
||||
|
||||
log_info "记录 binlog 位置: $binlog_file:$binlog_pos"
|
||||
|
||||
cat > "$position_file" << EOF
|
||||
# MySQL Binlog Position
|
||||
# 备份时间: $BACKUP_TIMESTAMP
|
||||
# 用于下次增量备份的起始位置
|
||||
|
||||
BINLOG_FILE=$binlog_file
|
||||
BINLOG_POSITION=$binlog_pos
|
||||
EOF
|
||||
}
|
||||
|
||||
# ----------------------------------------------------------------------------
|
||||
# 保存备份元数据
|
||||
# ----------------------------------------------------------------------------
|
||||
save_metadata() {
|
||||
local base_dir="$1"
|
||||
local metadata_file="${BACKUP_DIR}/metadata.txt"
|
||||
|
||||
log_info "保存备份元数据"
|
||||
|
||||
local end_time=$(date +%s)
|
||||
local duration=$(calculate_duration "$START_TIME" "$end_time")
|
||||
local backup_size=$(get_file_size "$BACKUP_DIR")
|
||||
|
||||
cat > "$metadata_file" << EOF
|
||||
# MySQL 增量备份元数据
|
||||
# ========================================
|
||||
|
||||
备份类型: 增量备份 (Incremental Backup)
|
||||
备份时间: $BACKUP_TIMESTAMP
|
||||
备份目录: $BACKUP_NAME
|
||||
备份大小: $backup_size
|
||||
执行耗时: $duration
|
||||
基准备份: $base_dir
|
||||
|
||||
MySQL 服务器: ${MYSQL_HOST}:${MYSQL_PORT}
|
||||
MySQL 用户: $MYSQL_USER
|
||||
|
||||
备份选项:
|
||||
- 压缩: $ENABLE_COMPRESS
|
||||
- 压缩工具: $COMPRESS_TOOL
|
||||
|
||||
备份状态: 成功
|
||||
EOF
|
||||
|
||||
# 记录基准备份路径 (用于恢复时的依赖链)
|
||||
echo "$base_dir" > "${BACKUP_DIR}/base_backup_path.txt"
|
||||
|
||||
log_info "元数据已保存"
|
||||
}
|
||||
|
||||
# ----------------------------------------------------------------------------
|
||||
# 清理过期备份
|
||||
# ----------------------------------------------------------------------------
|
||||
cleanup_expired_backups() {
|
||||
log_info "检查过期备份..."
|
||||
cleanup_old_backups "$INCREMENTAL_BACKUP_DIR" "$INCREMENTAL_BACKUP_RETENTION_DAYS"
|
||||
}
|
||||
|
||||
# ----------------------------------------------------------------------------
|
||||
# 主函数
|
||||
# ----------------------------------------------------------------------------
|
||||
main() {
|
||||
# 记录开始时间
|
||||
START_TIME=$(date +%s)
|
||||
|
||||
# 解析参数
|
||||
parse_args "$@"
|
||||
|
||||
# 初始化
|
||||
init_backup
|
||||
|
||||
# 查找基准备份
|
||||
local base_backup=$(find_base_backup)
|
||||
log_info "基准备份: $base_backup"
|
||||
|
||||
# 执行 binlog 备份
|
||||
backup_binlogs "$base_backup"
|
||||
|
||||
# 保存元数据
|
||||
save_metadata "$base_backup"
|
||||
|
||||
# 清理过期备份
|
||||
cleanup_expired_backups
|
||||
|
||||
# 计算总耗时
|
||||
local end_time=$(date +%s)
|
||||
local duration=$(calculate_duration "$START_TIME" "$end_time")
|
||||
local backup_size=$(get_file_size "$BACKUP_DIR")
|
||||
|
||||
log_info "============================================================"
|
||||
log_info "MySQL 增量备份完成"
|
||||
log_info "============================================================"
|
||||
log_info "备份目录: $BACKUP_DIR"
|
||||
log_info "备份大小: $backup_size"
|
||||
log_info "执行耗时: $duration"
|
||||
log_info "基准备份: $base_backup"
|
||||
log_info "============================================================"
|
||||
|
||||
# 发送成功通知
|
||||
send_notification "[成功] MySQL 增量备份" "备份完成\n目录: $BACKUP_DIR\n大小: $backup_size\n耗时: $duration"
|
||||
|
||||
return 0
|
||||
}
|
||||
|
||||
# 执行主函数
|
||||
main "$@"
|
||||
Reference in New Issue
Block a user