xtrabackup是一个MySQL备份还原的常用工具，实际使用过程应该都是shell或者Python封装的自动化脚本，尤其是备份。 对还原来说，对于基于完整和增量备份的还原，还原差异备份需要指定增
xtrabackup是一个MySQL备份还原的常用工具，实际使用过程应该都是shell或者Python封装的自动化脚本，尤其是备份。对还原来说，对于基于完整和增量备份的还原，还原差异备份需要指定增量备份等等一系列容易出错的手工操作，以及binlog的还原等，如果纯手工操作的话非常麻烦。即便是你记性非常好，对xtrabackup非常熟悉，纯手工操作的话，非常容易出错，其实也上网找过，还原没有发现太好用的自动化还原脚本。于是就自己用Python封装了xtrabackup备份和还原的过程，可以做到自动化备份，基于时间点的自动化还原等等。
需要对xtrabackup有一定的了解，包括流式备份，压缩备份，Xtrabackup还原，mysqlbinlog还原等等。
备份
1，基于xtrabackup的流式压缩备份。2，周六/或者任意时间的第一次备份为完整备份，其他时间为基于上一次备份的增量备份。3，将备份开始时间，结束时间，备份路径等信息写入一个日志文件，方便后续自动化还原的时候解析。
效果如下：不管是什么时候，第一次必须为完整备份，然后根据上述规则，继续执行备份的话为基于最新一次备份的增量备份，每备份完成后生成修改备份日志列表信息。
实现：
# -*- coding: utf-8 -*-import osimport timeimport datetimeimport sysimport socketimport shutilimport logging
logging.basicConfig(level=logging.INFO #handlers={logging.FileHandler(filename='backup_log_info.log', mode='a', encoding='utf-8')} )
host = "127.0.0.1"port = "7000"user = "root"password = "root"cnf_file = "/usr/local/mysql57_data/mysql7000/etc/my.cnf"backup_dir = "/usr/local/backupdata"backupfilelist = os.path.join(backup_dir,"backupfilelist.log")backup_keep_days = 15
#获取备份类型，周六进行完备，平时增量备份，如果没有全备，执行完整备份def get_backup_type(): backup_type = None if os.path.exists(backupfilelist): with open(backupfilelist, 'r') as f: lines = f.readlines() if(lines): last_line = lines[-1] #get last backup name if(last_line): if(time.localtime().tm_wday==6): backup_type = "full" else: backup_type = "incr" else: backup_type = "full" else: backup_type = "full" else: #full backup when first backup open(backupfilelist, "a").close() backup_type = "full" return backup_type
#获取最后一次备份信息def get_last_backup(): last_backup = None if os.path.exists(backupfilelist): with open(backupfilelist, 'r') as f: lines = f.readlines() last_line = lines[-1] # get last backup name if (last_line): last_backup = os.path.join(backup_dir, last_line.split("|")[-1]) return last_backup.replace("n","")
#探测实例端口号def get_mysqlservice_status(): mysql_stat = 0 s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) result = s.connect_ex((host, int(port))) #port os open if (result == 0): mysql_stat = 1 return mysql_stat
#清理过期的历史备份信息def clean_expired_file(): for backup_name in os.listdir(backup_dir): if os.path.isdir(backup_name): bak_datetime = datetime.datetime.strptime(backup_name.replace("_full","").replace("_incr",""), '%Y%m%d%H%M%S') if(bak_datetime<datetime.datetime.now() - datetime.timedelta(days=backup_keep_days)): shutil.rmtree(os.path.join(backup_dir, backup_name))
#完整备份def full_backup(backup_file_name): os.system("[ ! -d {0}/{1} ] && mkdir -p {0}/{1}".format(backup_dir,backup_file_name)) logfile = os.path.join(backup_dir, "{0}/{1}/backuplog.log".format(backup_dir,backup_file_name)) backup_commond = ''' innobackupex --defaults-file={0} --no-lock {1}/{6} --user={2} --password={3} --host="{4}" --port={5} --tmpdir={1}/{6} --stream=xbstream --compress --compress-threads=8 --parallel=4 --extra-lsndir={1}/{6} > {1}/{6}/{6}.xbstream 2>{7} '''. format(cnf_file,backup_dir,user,password,host,port,backup_file_name,logfile) execute_result = os.system(backup_commond) return execute_result
#增量备份def incr_backup(backup_file_name): os.system("[ ! -d {0}/{1} ] && mkdir -p {0}/{1}".format(backup_dir, backup_file_name)) current_backup_dir = "{0}/{1}".format(backup_dir, backup_file_name) logfile = os.path.join(backup_dir, "{0}/{1}/backuplog.log".format(backup_dir, backup_file_name)) #增量备份基于上一个增量/完整备份 incremental_basedir = get_last_backup() backup_commond = '''innobackupex --defaults-file={0} --no-lock {6} --user={2} --password={3} --host={4} --port={5} --stream=xbstream --tmpdir={6} --compress --compress-threads=8 --parallel=4 --extra-lsndir={6} --incremental --incremental-basedir={7} 2> {8} > {6}/{9}.xbstream ''' .format(cnf_file,backup_dir,user,password,host,port,current_backup_dir,incremental_basedir,logfile,backup_file_name) # print(backup_commond) execute_result = os.system(backup_commond) return execute_result
#刷新binlog，意义不大，原本计划在完整备份之后执行一个binlog的切换，暂时弃用def flush_log(): flush_log_commond = ''' mysql -h${0} -u${1} - p${2} -P${1} mysql - e"flush logs" '''.format(user,password,host,port) os.system(flush_log_commond)
if __name__ == '__main__': mysql_stat = get_mysqlservice_status() backup_type = get_backup_type() if mysql_stat <= 0 : logging.info("mysql instance is inactive,backup exit") sys.exit(1) try: start_time = datetime.datetime.now().strftime('%Y%m%d%_H%M%S') logging.info(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')+"--------start backup") #flush_log() backup_file_name = start_time execute_result = None if(backup_type == "full"): backup_file_name = backup_file_name+"_full" logging.info("execute full backup......") execute_result = full_backup(backup_file_name) if (execute_result == 0): logging.info(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S') + "--------begin cleanup history backup") logging.info("execute cleanup backup history......") clean_expired_file() logging.info(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S') + "--------finsh cleanup history backup") else: backup_file_name = backup_file_name + "_incr" logging.info("execute incr backup......") execute_result = incr_backup(backup_file_name) if(execute_result==0): finish_time = datetime.datetime.now().strftime('%Y%m%d%_H%M%S') backup_info = start_time+"|"+finish_time+"|"+start_time+ "_" + backup_type with open(backupfilelist, 'a+') as f: f.write(backup_info + 'n') logging.info(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')+"--------finish backup") else: logging.info(datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S') + "--------xtrabackup failed.please check log") except: raise sys.exit(1)
还原
说直白一点，以这里的基于时间点或者是position的还原，就是一个不断找文件的过程，1，首先任何还原，都需要一个创建于还原点前的完整备份。2，基于上述完整备份，利用还原的时间点与xtrbackup的备份日志去做对比来获取所需的增量备份（0个或者1个或者多个）。3，基于上面两步找到的（完整+增量）备份，利用最后一个备份的position，用于第一个binlog还原时指定start-position， 同时利用binlog的最后修改时间与还原的时间点对比，决定使用那些binlog，同时最后一个binlog要指定stop-datime= 还原的时间点
1，如何还原时间点的最新的一个完整备份备份的时候维护一个备份信息，如下,这里是backfilelist.log，包括备份开始时间，结束时间，备份类型，备份路径等。可以根据备份开始时间，找到第一个早于还原时间点的完整备份
2，如果找到恢复所需要的差异备份同1，从完整备份开始，依次向后找各个增量备份，直到最后一个早于还原时间点的差异备份，可能有一个或者多个
3，如何找到差异备份之后，需要哪些binlog基于binlog文件自身的最后修改时间属性信息，从2中找到的最后一个差异备份的时间，开始向后依次找binlog，可能有一个或者多个
自动还原demo
如下是一个基于时间点来还原数据库的demo，没写入两条数据，执行一次备份（上述备份会自动区分完整备份或者差异备份）三次备份之后，继续写两条数据，flush logs,然后继续分两次分别写两条数据，目的是将数据分散到不同的binlog中，最后删除全部数据然后基于删除数据之前的时间点来自动生成还原数据库的shell，执行shell即可达到还原数据库的目的。
如下执行基于时间点的rextrabackup.py文件之后，时间点为"2019-08-01 18:50:59"，也就是发生删除操作的前一个时间点，来生成的还原信息。其实只需要重定向到一个shell文件中，执行shell文件即可自动化还原，或者直接在python脚本中执行这些命令，即可自动化完成还原操作。这里为了显示，打印了出来。
可以发现，基于时间点的还原，找到的文件是预期的：1个完整备份，2个增量备份，2个binlog日志中的一部分数据，其中binlog日志还原的start-position成功地衔接到最后一个增量备份的position，同时最后一个binlog日志的还原停留在指定的时间点。
自动生成的shell还原代码
################uncompress backup file###################innobackupex --apply-log --redo-only /temp/restoretmp/20190801184134_fullinnobackupex --apply-log --redo-only /temp/restoretmp/20190801184134_full --incremental-dir=/temp/restoretmp/20190801184335_incinnobackupex --apply-log --redo-only /temp/restoretmp/20190801184134_full --incremental-dir=/temp/restoretmp/20190801184518_incinnobackupex --apply-log /temp/restoretmp/20190801184134_full################stop mysql service###################systemctl stop mysqld_7000####################backup current database file###########################mv /usr/local/mysql57_data/mysql7000/data /usr/local/mysql57_data/mysql7000/data_20190801185855mkdir /usr/local/mysql57_data/mysql7000/datachown -R mysql.mysql /usr/local/mysql57_data/mysql7000/data################restore backup data###################innobackupex --defaults-file=/usr/local/mysql57_data/mysql7000/etc/my.cnf --copy-back --rsync /temp/restoretmp/20190801184134_fullchown -R mysql.mysql /usr/local/mysql57_data/mysql7000/data################stop mysql service###################systemctl start mysqld_7000################restore data from binlog###################cd /usr/local/mysql57_data/mysql7000/log/bin_logmysqlbinlog mysql_bin_1300.000001 --skip-gtids=true --start-position=982 | mysql mysql -h127.0.0.1 -uroot -proot -P7000mysqlbinlog mysql_bin_1300.000002 --skip-gtids=true --stop-datetime="2019-08-01 18:50:59" | mysql -h127.0.0.1 -uroot -proot -P7000
日志信息
实现
# -*- coding: utf-8 -*-import osimport timeimport datetimeimport sysimport socketimport logging
logging.basicConfig(level=logging.INFO #handlers={logging.FileHandler(filename='restore_log_info.log', mode='a', encoding='utf-8')} )
host = "127.0.0.1"port = "7000"user = "root"password = "root"instance_name = "mysqld_7000"stop_at = "2019-08-01 18:50:59"cnf_file = "/usr/local/mysql57_data/mysql7000/etc/my.cnf"backup_dir = "/usr/local/backupdata/"dest_dir = "/temp/restoretmp/"xtrabackuplog_name = "backuplog.log"backupfilelist = os.path.join(backup_dir,"backupfilelist.log")
#根据key值，获取MySQL配置文件中的valuedef get_config_value(key): value = None if not key: return value if os.path.exists(cnf_file): with open(cnf_file, 'r') as f: for line in f: if (line.split("=")[0]): if(line[0:1]!="#" and line[0:1]!="["): if (key==line.split("=")[0].strip()): value =line.split("=")[1].strip() return value
def stop_mysql_service(): print("################stop mysql service###################") print("systemctl stop {}".format(instance_name))
def start_mysql_service(): print("################stop mysql service###################") print("systemctl start {0}".format(instance_name))
#返回备份日志中的最新的一个早于stop_at时间的完整备份，以及其后面的增量备份def get_restorefile_list(): list_backup = [] list_restore_file = [] if os.path.exists(backupfilelist): with open(backupfilelist, 'r') as f: lines = f.readlines() for line in lines: list_backup.append(line.replace("n","")) if (list_backup): for i in range(len(list_backup) - 1, -1, -1): list_restore_file.append(list_backup[i]) backup_name = list_backup[i].split("|")[2] if "full" in backup_name: full_backup_time = list_backup[i].split("|")[1] if(stop_at<full_backup_time): break else: list_restore_file = None #restore file in the list_restore_log list_restore_file.reverse() return list_restore_file
#解压缩需要还原的备份文件，包括一个完整备份以及N个增量备份（N>=0）def uncompress_backup_file(): print("################uncompress backup file###################") list_restore_backup = get_restorefile_list()
#如果没有生成时间早于stop_at的完整备份，无法恢复，退出 if not list_restore_backup: raise("There is no backup that can be restored") exit(1)
for restore_log in list_restore_backup: #解压备份文件 backup_name = restore_log.split("|")[2] backup_path = restore_log.split("|")[2] backup_full_name = os.path.join(backup_dir,backup_path,backup_name) backup_path = os.path.join(backup_dir,restore_log.split("|")[-1]) #print('''[ ! -d {0} ] && mkdir -p {0}'''.format(os.path.join(dest_dir,backup_name))) os.system('''[ ! -d {0} ] && mkdir -p {0}'''.format(os.path.join(dest_dir,backup_name))) #print("xbstream -x < {0}.xbstream -C {1}".format(backup_full_name,os.path.join(dest_dir,backup_name))) os.system("xbstream -x < {0}.xbstream -C {1}".format(backup_full_name,os.path.join(dest_dir,backup_name))) #print("cd {0}".format(os.path.join(dest_dir,backup_name))) os.system("cd {0}".format(os.path.join(dest_dir,backup_name))) #print('''for f in `find {0}/ -iname "*.qp"`; do qpress -dT4 $f $(dirname $f) && rm -f $f; done '''.format(os.path.join(dest_dir,backup_name))) os.system('''for f in `find {0}/ -iname "*.qp"`; do qpress -dT4 $f $(dirname $f) && rm -f $f; done'''.format(os.path.join(dest_dir,backup_name)))
current_backup_begin_time = None current_backup_end_time = None #比较当前备份的结束时间和stop_at,如果当前备份开始时间小于stop_at并且结束时间大于stop_at，解压缩备份结束 with open(os.path.join(dest_dir,backup_name,"xtrabackup_info"), 'r') as f: for line in f: if line and line.split("=")[0].strip()=="start_time": current_backup_begin_time = line.split("=")[1].strip() if line and line.split("=")[0].strip()=="end_time": current_backup_end_time = line.split("=")[1].strip() #按照stop_at时间点还原的最后一个数据库备份,结束从第一个完整备份开始的解压过程 if current_backup_begin_time<=stop_at<=current_backup_end_time: break
#返回最后一个备份文件，需要备份文件中的xtrabackup_info，解析出当前备份的end_time，从而确认需要哪些binlog return backup_name
#根据返回最后一个备份文件，需要备份文件中的xtrabackup_info，结合stop_at，确认需要还原的binlog文件，以及binlog的position信息def restore_database_binlog(last_backup_file): print("################restore data from binlog###################") binlog_dir = get_config_value("log-bin") if not (backup_dir): binlog_dir = get_config_value("log_bin") print("cd {0}".format(os.path.dirname(binlog_dir)))
last_backup_file =os.path.join(dest_dir,last_backup_file,"xtrabackup_info") #parse backuplog.log and get binlog name and position
backup_position_binlog_file = None backup_position = None with open(last_backup_file, 'r') as f: lines = f.readlines() for line in lines: if "binlog_pos = filename " in line: backup_position_binlog_file = line.replace("binlog_pos = filename ", "").split(",")[0] backup_position_binlog_file = backup_position_binlog_file.replace("'", "") backup_position = line.replace("binlog_pos = filename ", "").split(",")[1].strip() backup_position = backup_position.split(" ")[1].replace("'", "") pass else: continue # /usr/local/mysql57_data/mysql8000/log/bin_log/mysql_bin_1300 binlog_config = get_config_value("log-bin") binlog_path = os.path.dirname(binlog_config) binlog_files = os.listdir(binlog_path)
#如果没有找到binlog，忽略binlog的还原 if not binlog_files: exit(1)
#对binlog文件排序，按顺序遍历binlog，获取binlog的最后的修改时间，与stop_at做对比，判断还原的过程是否需要某个binlogfile binlog_files.sort()
binlog_files_for_restore = [] # 恢复数据库的指定时间点 stop_at_time = datetime.datetime.strptime(stop_at, '%Y-%m-%d %H:%M:%S') for binlog in binlog_files: if (".index" in binlog or "relay" in binlog): continue
#保留最后一个备份中的binlog，以及其后面的binlog，这部分binlog会在还原的时候用到 if (int(binlog.split(".")[-1]) >= int(backup_position_binlog_file.split(".")[-1])): binlog_files_for_restore.append(binlog)
binlog_file_count = 0 #第一个文件，从上最后一个差异备份的position位置开始，最后一个文件，需要stop_at到指定的时间 for binlog in binlog_files_for_restore: if not os.path.isdir(binlog): #binlog物理文件的最后修改时间 binlog_file_updatetime = datetime.datetime.strptime(time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(os.stat(binlog_path+"/"+binlog).st_mtime)),'%Y-%m-%d %H:%M:%S') #判断binlog的生成时间，是否大于stop_at，对于修改时间大于stop_at的日志，需要全部还原，不需要stop_at指定截止点 if stop_at_time > binlog_file_updatetime : if (binlog_file_count < 1): if (len(binlog_files_for_restore) == 1): # 找到差异备份之后的第一个binlog，需要根据差异备份的position，来过来第一个binlog文件 restore_commond = '''mysqlbinlog {0} --skip-gtids=true --start-position={1} --stop-datetime="{2}" | mysql mysql -h{3} -u{4} -p{5} -P{6}''' .format(binlog, backup_position, stop_at, host, user, password, port) print(restore_commond) binlog_file_count = binlog_file_count + 1 else: # 找到差异备份之后的第一个binlog，需要根据差异备份的position，来过来第一个binlog文件 restore_commond = '''mysqlbinlog {0} --skip-gtids=true --start-position={1} | mysql mysql -h{2} -u{3} -p{4} -P{5}''' .format(binlog, backup_position, host, user, password, port) print(restore_commond) binlog_file_count = binlog_file_count + 1 else: # 从第二个文件开始，binlog需要全部还原 restore_commond = '''mysqlbinlog {0} --skip-gtids=true | mysql mysql -h{1} -u{2} -p{3} -P{4}''' .format(binlog, host, user, password, port) print(restore_commond) binlog_file_count = binlog_file_count + 1 else: if (binlog_file_count < 1): restore_commond = '''mysqlbinlog {0} --skip-gtids=true --start-position={1} --stop-datetime={2} | mysql -h{3} -u{4} -p{5} -P{6}'''.format(binlog, backup_position,stop_at,host,user,password,port) print(restore_commond) binlog_file_count = binlog_file_count + 1 else: if (binlog_file_count >= 1): restore_commond = '''mysqlbinlog {0} --skip-gtids=true --stop-datetime="{1}" | mysql -h{2} -u{3} -p{4} -P{5}'''.format(binlog, stop_at,host,user,password,port) print(restore_commond) binlog_file_count = binlog_file_count + 1 break
def apply_log_for_backup(): list_restore_backup = get_restorefile_list() start_flag = 1 full_backup_path = None
for current_backup_file in list_restore_backup: #解压备份文件 current_backup_name = current_backup_file.split("|")[2] current_backup_fullname = os.path.join(dest_dir, current_backup_name) if(start_flag==1): full_backup_path = current_backup_fullname start_flag = 0 print("innobackupex --apply-log --redo-only {0}".format(full_backup_path)) else: print("innobackupex --apply-log --redo-only {0} --incremental-dir={1}".format(full_backup_path,current_backup_fullname)) #apply_log for full backup at last(remove --read-only parameter) print("innobackupex --apply-log {0}".format(full_backup_path))
def restore_backup_data(): print("####################backup current database file###########################") datadir_path = get_config_value("datadir") print("mv {0} {1}".format(datadir_path,datadir_path+"_"+ datetime.datetime.now().strftime('%Y%m%d%H%M%S'))) print("mkdir {0}".format(datadir_path)) print("chown -R mysql.mysql {0}".format(datadir_path)) print("################restore backup data###################") list_restore_backup = get_restorefile_list() full_restore_path= dest_dir + list_restore_backup[0].split("|")[-1].replace(".xbstream","") print("innobackupex --defaults-file={0} --copy-back --rsync {1}".format(cnf_file,full_restore_path)) print("chown -R mysql.mysql {0}".format(datadir_path))
def restore_database(): #解压缩需要还原的备份文件 last_backup_file_path = uncompress_backup_file() #对备份文件apply-log apply_log_for_backup() #停止mysql服务 stop_mysql_service() #恢复备份 restore_backup_data() #启动MySQL服务 start_mysql_service() #从binlog中恢复数据 restore_database_binlog(last_backup_file_path)
if __name__ == '__main__': restore_database()
最后不要忘了清理战场：1，解压缩的备份文件还留在指定的路径中，2，还原之前备份的data文件，以data_日期命名的文件，也没有清理
挤时间写出来的，粗略测了一下没有问题，以实现功能为主，没有进一步封装，后续会以此为基础进行优化。
