Oracle RMAN 备份与恢复

目录

• 1. 简介
• 2. 环境准备
• 3. 全量备份（Full Backup）
• 4. 增量备份（Incremental Backup）
• 5. 恢复操作
  • 5.1 完全恢复（数据库崩溃后）
  • 5.2 表空间级恢复
  • 5.3 不完全恢复（时间点恢复）
• 6. 自动化备份脚本
  • 6.1 全量备份脚本
  • 6.2 增量 Level 1 备份脚本
  • 6.3 定期调度（crontab）
• 7. 注意事项

简介

RMAN（Recovery Manager）是 Oracle 提供的官方备份与恢复工具，支持：

• 物理备份（数据文件、控制文件、归档日志）
• 块级增量备份
• 自动化恢复
• 与 Oracle Secure Backup、NFS、磁带库等集成

本文重点讲解如何通过 RMAN 实现 全量 + 增量备份策略，并提供可直接用于生产环境的脚本。

环境准备

确保以下条件满足：

# 设置环境变量（建议写入 ~/.bash_profile）
export ORACLE_SID=orcl
export ORACLE_HOME=/u01/app/oracle/product/19.0.0/dbhome_1
export PATH=$ORACLE_HOME/bin:$PATH
export NLS_LANG=AMERICAN_AMERICA.AL32UTF8

启用归档模式（必须）：

SQL> SHUTDOWN IMMEDIATE;
SQL> STARTUP MOUNT;
SQL> ALTER DATABASE ARCHIVELOG;
SQL> ALTER DATABASE OPEN;
SQL> ARCHIVE LOG LIST;  -- 确认处于 Archive Mode

配置 RMAN 默认参数（可选但推荐）：

RMAN> CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 7 DAYS;
RMAN> CONFIGURE CONTROLFILE AUTOBACKUP ON;
RMAN> CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '/backup/rman/cf_%F';
RMAN> CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/backup/rman/%U';

✅ 为什么重要？
这些配置让 RMAN 自动化程度更高，减少手动指定路径的错误，也便于恢复时定位文件。

全量备份（Full Backup）

全量备份 = Level 0 增量备份（Oracle 中全备通常用 BACKUP INCREMENTAL LEVEL 0 实现）。

RMAN 命令

RUN {
  ALLOCATE CHANNEL c1 TYPE DISK;
  BACKUP INCREMENTAL LEVEL 0 
    DATABASE 
    PLUS ARCHIVELOG 
    DELETE INPUT;
  BACKUP CURRENT CONTROLFILE;
  RELEASE CHANNEL c1;
}

📌 关键概念：

• Level 0 ≠ FULL？实际上在恢复时，Level 0 被当作全量使用。
• PLUS ARCHIVELOG DELETE INPUT 是生产环境常用组合，但务必监控归档空间！

增量备份（Incremental Backup）

Oracle 支持两种增量：

• Level 0：包含所有数据块（等同于全量）
• Level 1：
  • Differential（默认）：备份自上次 Level 0 或 Level 1 以来变化的块
  • Cumulative：备份自上次 Level 0 以来所有变化的块

Level 1 差异增量备份（推荐）

RUN {
  ALLOCATE CHANNEL c1 TYPE DISK;
  BACKUP INCREMENTAL LEVEL 1 
    DATABASE 
    PLUS ARCHIVELOG 
    DELETE INPUT;
  RELEASE CHANNEL c1;
}

• LEVEL 1：只备份自上一次 Level 0 或 Level 1 以来发生变化的数据块（差异增量）。
• 默认是 Differential（差异），不是 Cumulative。
• 例如：
  • 周日：Level 0
  • 周一：Level 1 → 备周一变化
  • 周二：Level 1 → 备周二变化（不是周一周二总和）
• 恢复时需：Level 0 + 所有后续 Level 1 + 归档日志。

✅ 优点：节省备份时间和空间。
❗ 风险：若中间某天 Level 1 丢失，之后所有增量都无法用。

恢复操作

完全恢复（数据库崩溃后）

假设整个数据库丢失（如磁盘故障），需从备份完全恢复：

# 启动到 nomount
RMAN> STARTUP FORCE NOMOUNT;

# 恢复控制文件（若启用了 autobackup）
RMAN> RESTORE CONTROLFILE FROM '/backup/rman/cf_c-1234567890-20250101-00';

RMAN> ALTER DATABASE MOUNT;

# 恢复数据库
RMAN> RESTORE DATABASE;

# 应用归档日志进行恢复
RMAN> RECOVER DATABASE;

# 打开数据库（需 resetlogs，因控制文件是恢复的）
RMAN> ALTER DATABASE OPEN RESETLOGS;

⚠️ 注意：OPEN RESETLOGS 会重置日志序列号，之后需立即做一次 Level 0 备份！

表空间级恢复

RMAN> SQL 'ALTER TABLESPACE users OFFLINE IMMEDIATE';
RMAN> RESTORE TABLESPACE users;
RMAN> RECOVER TABLESPACE users;
RMAN> SQL 'ALTER TABLESPACE users ONLINE';

不完全恢复（时间点恢复）

例如恢复到 2025-01-05 14:00:00：

RMAN> STARTUP MOUNT;
RMAN> RUN {
  SET UNTIL TIME "TO_DATE('2025-01-05 14:00:00', 'YYYY-MM-DD HH24:MI:SS')";
  RESTORE DATABASE;
  RECOVER DATABASE;
  ALTER DATABASE OPEN RESETLOGS;
}

自动化备份脚本

全量备份脚本（rman_full_backup.sh）

#!/bin/bash
# Oracle RMAN Level 0 Backup Script (Optimized)
# Author: DBA Team
# Date: 2026-01-06

# --- 1. 加载环境变量 ---
source /home/oracle/.bash_profile

# --- 2. 强制设置关键环境变量 ---
export ORACLE_SID=orcl1
export DBNAME=orcl
export NLS_LANG=AMERICAN_AMERICA.AL32UTF8  # 防止日期格式或字符集问题

# --- 3. 时间变量 ---
year=$(date "+%Y")
month=$(date "+%m")
day=$( date "+%d")
hour=$(date "+%H")
min=$(date "+%M")
sec=$(date "+%S")
bakdate=${year}${month}${day}
baktime=${hour}${min}${sec}

# --- 4. 路径定义 ---
BACKUP_DIR=/orabak/scsbgjb/${bakdate}
DATABAK=${BACKUP_DIR}/databak
ARCHBAK=${BACKUP_DIR}/archbak
SCRIPT_DIR=/home/oracle/enmo/backup/scripts
LOG_DIR=/home/oracle/enmo/backup/log

CMDFILE=${SCRIPT_DIR}/scsbgjb_level_0_${bakdate}_${baktime}.rman
LOGFILE=${LOG_DIR}/${bakdate}_${baktime}_level_0.log

# --- 5. 创建目录 ---
mkdir -p "${DATABAK}" "${ARCHBAK}" "${SCRIPT_DIR}" "${LOG_DIR}"

# --- 6. 记录开始时间 ---
echo "[$(date)] Starting RMAN Level 0 Backup for DB: ${DBNAME} (SID: ${ORACLE_SID})" | tee "${LOGFILE}"

# --- 7. 生成 RMAN 命令文件 ---
cat > "${CMDFILE}" << EOF
RUN {
  # 分配 10 个并行通道（根据 I/O 能力调整）
  ALLOCATE CHANNEL ch1 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch2 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch3 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch4 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch5 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch6 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch7 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch8 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch9 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch10 DEVICE TYPE DISK;

  # 强制归档当前日志，确保一致性
  SQL 'ALTER SYSTEM ARCHIVE LOG CURRENT';

  # 备份数据库（Level 0 + 压缩）
  BACKUP AS COMPRESSED BACKUPSET
    INCREMENTAL LEVEL 0
    FILESPERSET 20
    FORMAT '${DATABAK}/${DBNAME}_level_0_%U_%T'
    DATABASE;

  # 备份所有尚未备份过的归档日志（更安全）
  BACKUP AS COMPRESSED BACKUPSET
    SKIP INACCESSIBLE
    FILESPERSET 20
    FORMAT '${ARCHBAK}/${DBNAME}_arch_%U_%T'
    ARCHIVELOG ALL NOT BACKED UP 1 TIMES;

  # 显式备份控制文件和 SPFILE（即使启用了 autobackup）
  BACKUP CURRENT CONTROLFILE FORMAT '${BACKUP_DIR}/${DBNAME}_control_bak_%T';
  BACKUP SPFILE TAG 'spfile' FORMAT '${BACKUP_DIR}/${DBNAME}_spfile_%U_%T';

  # 释放通道
  RELEASE CHANNEL ch1; RELEASE CHANNEL ch2; RELEASE CHANNEL ch3; RELEASE CHANNEL ch4;
  RELEASE CHANNEL ch5; RELEASE CHANNEL ch6; RELEASE CHANNEL ch7; RELEASE CHANNEL ch8;
  RELEASE CHANNEL ch9; RELEASE CHANNEL ch10;
}

# 清理：仅本次使用 30 天保留策略（不修改全局配置）
REPORT OBSOLETE RECOVERY WINDOW OF 30 DAYS;
DELETE NOPROMPT OBSOLETE RECOVERY WINDOW OF 30 DAYS;

# 校验并清理失效备份
CROSSCHECK BACKUP;
CROSSCHECK ARCHIVELOG ALL;
DELETE NOPROMPT EXPIRED BACKUP;
DELETE NOPROMPT EXPIRED ARCHIVELOG;
EOF

# --- 8. 执行 RMAN ---
echo "[$(date)] Executing RMAN command from: ${CMDFILE}" >> "${LOGFILE}"
$ORACLE_HOME/bin/rman TARGET / CMDLINE="SET ECHO ON" LOG="${LOGFILE}" < "${CMDFILE}"

# --- 9. 检查执行结果 ---
if [ ${?} -eq 0 ]; then
  echo "[$(date)] ✅ RMAN Level 0 Backup SUCCESSFUL." >> "${LOGFILE}"
  echo "Backup completed successfully. Log: ${LOGFILE}"
else
  echo "[$(date)] ❌ RMAN Level 0 Backup FAILED!" >> "${LOGFILE}"
  echo "ERROR: Backup failed! Check log: ${LOGFILE}" >&2
  exit 1
fi

增量 Level 1 备份脚本（rman_incr_backup.sh）

#!/bin/bash
# Oracle RMAN Level 1 Incremental Backup Script (Optimized)
# Author: DBA Team
# Date: 2026-01-06

# --- 1. 加载环境变量 ---
source /home/oracle/.bash_profile

# --- 2. 强制设置关键环境变量 ---
export ORACLE_SID=orcl1
export DBNAME=orcl
export NLS_LANG=AMERICAN_AMERICA.AL32UTF8  # 避免日期/字符集问题

# --- 3. 时间变量 ---
year=$(date "+%Y")
month=$(date "+%m")
day=$(date "+%d")
hour=$(date "+%H")
min=$(date "+%M")
sec=$(date "+%S")
bakdate=${year}${month}${day}
baktime=${hour}${min}${sec}

# --- 4. 路径定义 ---
BACKUP_DIR=/orabak/scsbgjb/${bakdate}
DATABAK=${BACKUP_DIR}/databak
ARCHBAK=${BACKUP_DIR}/archbak
SCRIPT_DIR=/home/oracle/enmo/backup/scripts
LOG_DIR=/home/oracle/enmo/backup/log

CMDFILE=${SCRIPT_DIR}/scsbgjb_level_1_${bakdate}_${baktime}.rman
LOGFILE=${LOG_DIR}/${bakdate}_${baktime}_level_1.log

# --- 5. 创建目录 ---
mkdir -p "${DATABAK}" "${ARCHBAK}" "${SCRIPT_DIR}" "${LOG_DIR}"

# --- 6. 记录开始时间 ---
echo "[$(date)] Starting RMAN Level 1 Incremental Backup for DB: ${DBNAME} (SID: ${ORACLE_SID})" | tee "${LOGFILE}"

# --- 7. 生成 RMAN 命令文件 ---
cat > "${CMDFILE}" << EOF
RUN {
  # 分配 10 个并行通道
  ALLOCATE CHANNEL ch1 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch2 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch3 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch4 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch5 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch6 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch7 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch8 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch9 DEVICE TYPE DISK;
  ALLOCATE CHANNEL ch10 DEVICE TYPE DISK;

  # 强制切换日志，确保最新变更被归档
  SQL 'ALTER SYSTEM ARCHIVE LOG CURRENT';

  # Level 1 增量备份（仅备份自上次 Level 0/1 后变化的块）
  BACKUP AS COMPRESSED BACKUPSET
    INCREMENTAL LEVEL 1
    FILESPERSET 20
    FORMAT '${DATABAK}/${DBNAME}_level_1_%U_%T'
    DATABASE;

  # 备份所有尚未备份过的归档日志（比 sysdate-1 更可靠）
  BACKUP AS COMPRESSED BACKUPSET
    SKIP INACCESSIBLE
    FILESPERSET 20
    FORMAT '${ARCHBAK}/${DBNAME}_arch_%U_%T'
    ARCHIVELOG ALL NOT BACKED UP 1 TIMES;

  # 显式备份控制文件和 SPFILE（双重保障）
  BACKUP CURRENT CONTROLFILE FORMAT '${BACKUP_DIR}/${DBNAME}_control_bak_%T';
  BACKUP SPFILE TAG 'spfile' FORMAT '${BACKUP_DIR}/${DBNAME}_spfile_%U_%T';

  # 释放通道
  RELEASE CHANNEL ch1; RELEASE CHANNEL ch2; RELEASE CHANNEL ch3; RELEASE CHANNEL ch4;
  RELEASE CHANNEL ch5; RELEASE CHANNEL ch6; RELEASE CHANNEL ch7; RELEASE CHANNEL ch8;
  RELEASE CHANNEL ch9; RELEASE CHANNEL ch10;
}

# 清理：仅本次使用 30 天保留策略（不修改全局配置）
REPORT OBSOLETE RECOVERY WINDOW OF 30 DAYS;
DELETE NOPROMPT OBSOLETE RECOVERY WINDOW OF 30 DAYS;

# 校验并清理失效备份
CROSSCHECK BACKUP;
CROSSCHECK ARCHIVELOG ALL;
DELETE NOPROMPT EXPIRED BACKUP;
DELETE NOPROMPT EXPIRED ARCHIVELOG;
EOF

# --- 8. 执行 RMAN ---
echo "[$(date)] Executing RMAN command from: ${CMDFILE}" >> "${LOGFILE}"
$ORACLE_HOME/bin/rman TARGET / CMDLINE="SET ECHO ON" LOG="${LOGFILE}" < "${CMDFILE}"

# --- 9. 检查执行结果 ---
if [ ${?} -eq 0 ]; then
  echo "[$(date)] ✅ RMAN Level 1 Backup SUCCESSFUL." >> "${LOGFILE}"
  echo "Incremental backup completed successfully. Log: ${LOGFILE}"
else
  echo "[$(date)] ❌ RMAN Level 1 Backup FAILED!" >> "${LOGFILE}"
  echo "ERROR: Incremental backup failed! Check log: ${LOGFILE}" >&2
  exit 1
fi

赋予执行权限：

chmod +x rman_full_backup.sh rman_incr_backup.sh

定期调度（crontab）

编辑 crontab：

crontab -e

添加以下内容（每周日全备，其他天增量）：

# 每周日凌晨 2 点全量备份
0 2 * * 0 /home/oracle/scripts/rman_full_backup.sh

# 周一至周六凌晨 2 点增量备份
0 2 * * 1-6 /home/oracle/scripts/rman_incr_backup.sh

注意事项

• 归档日志必须保留：恢复依赖归档日志，确保磁盘空间充足。
• 测试恢复流程：定期在测试环境演练恢复，避免“备份成功但无法恢复”。
• 监控日志：检查 $BACKUP_LOG 是否有 RMAN- 错误。
• 保留策略：根据业务需求调整 RETENTION POLICY。
• 加密与压缩（可选）：

  CONFIGURE COMPRESSION ALGORITHM 'BASIC';
  CONFIGURE ENCRYPTION FOR DATABASE ON;