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       db4.8_hotbackup - Create "hot backup" or "hot failover" snapshots


       db4.8_hotbackup  [-cDuVv]  [-d data_dir ...] [-h home] [-l log_dir] [-P
       password] -b backup_dir


       The db4.8_hotbackup utility creates  "hot  backup"  or  "hot  failover"
       snapshots of Berkeley DB database environments.

       The db4.8_hotbackup utility performs the following steps:

              1.     If the -c option is specified, checkpoint the source home
                     database environment,  and  remove  any  unnecessary  log

              2.     If the target directory for the backup does not exist, it
                     is created with mode read-write-execute for the owner.

                     If the target directory for the backup does exist and the
                     -u  option  was  specified,  all  log files in the target
                     directory  are  removed;  if  the  -u  option   was   not
                     specified, all files in the target directory are removed.

              3.     If the -u option was  not  specified,  copy  application-
                     specific  files  found  in  the database environment home
                     directory,  or  any  directory  specified  using  the  -d
                     option, into the target directory for the backup.

              4.     Copy  all  log  files found in the directory specified by
                     the -l  option  (or  in  the  database  environment  home
                     directory,  if  no  -l  option  was  specified), into the
                     target directory for the backup.

              5.     Perform catastrophic recovery on the hot backup.

              6.     Remove any unnecessary log files from the hot backup.

       The db4.8_hotbackup utility does not resolve pending transactions  that
       are in the prepared state. Applications that use DB_TXN->prepare should
       specify  DB_RECOVER_FATAL  when  opening  the  environment,   and   run
       DB_ENV->txn_recover  to  resolve any pending transactions, when failing
       over to the hot backup.


       -b     Specify the target directory for the backup.

       -c     Before performing the snapshot, checkpoint the  source  database
              environment and remove any log files that are no longer required
              in that  environment.   To  avoid  making  catastrophic  failure
              impossible,  log  file  removal must be integrated with log file

       -d     Specify one or more source directories that  contain  databases;
              if  none  is  specified, the database environment home directory
              will be searched for database  files.   As  database  files  are
              copied  into  a  single  backup directory, files named the same,
              stored in different source  directories,  could  overwrite  each
              other when copied into the backup directory.

       -h     Specify  the  source  directory  for  the  backup,  that is, the
              database environment home directory.

       -l     Specify a source directory that contains log files; if  none  is
              specified,  the  database  environment  home  directory  will be
              searched for log files.

       -P     Specify an environment password.  Although Berkeley DB utilities
              overwrite  password  strings as soon as possible, be aware there
              may be a window of vulnerability on systems  where  unprivileged
              users  can see command-line arguments or where utilities are not
              able  to  overwrite  the  memory  containing  the   command-line

       -u     Update  a pre-existing hot backup snapshot by copying in new log
              files.  If the -u option is  specified,  no  databases  will  be
              copied into the target directory.

       -V     Write  the  library  version  number to the standard output, and

       -v     Run in verbose mode, listing operations as they are done.

       -D     Use the data directories listed in the  DB_CONFIG  configuration
              file  in  the source directory.   This option has three effects:
              First,  if  they  do  not  already  exist,  the  specified  data
              directories  will  be  created  relative to the target directory
              (with mode read-write-execute owner). Second, all files  in  the
              source  data  directories  will  be  copied  to  the target data
              directories.  If  the  DB_CONFIG  file  specifies  one  or  more
              absolute  pathnames,  files  in those source directories will be
              copied to the top-level target directory. Third,  the  DB_CONFIG
              configuration  file will be copied from the +source directory to
              the target directory, and subsequently used for configuration if
              recovery is run in the target directory.

       Care  should be taken with the -D option and data directories which are
       named relative to the source directory but are not subdirectories (that
       is,  the name includes the element "..")  Specifically, the constructed
       target directory names must be meaningful and distinct from the  source
       directory  names,  otherwise  running  recovery in the target directory
       might corrupt the source data files.

       It is an error to use absolute pathnames for data  directories  or  the
       log  directory in this mode, as the DB_CONFIG configuration file copied
       into the target directory would then point at  the  source  directories
       and running recovery would corrupt the source data files.

       The   db4.8_hotbackup  utility  uses  a  Berkeley  DB  environment  (as
       described for the -h  option,  the  environment  variable  DB_HOME,  or
       because  the  utility  was  run in a directory containing a Berkeley DB
       environment).  In order to avoid environment corruption  when  using  a
       Berkeley  DB  environment,  db4.8_hotbackup  should always be given the
       chance to detach from the environment and exit  gracefully.   To  cause
       db4.8_hotbackup  to release all environment resources and exit cleanly,
       send it an interrupt signal (SIGINT).

       The db4.8_hotbackup utility exits 0 on success,  and  >0  if  an  error


              If  the  -h option is not specified and the environment variable
              DB_HOME is set, it is used as the path of the database home,  as
              described in DB_ENV->open.


       Oracle  Corporation.  This  manual  page  was created based on the HTML
       documentation for  db_hotbackup  from  Sleepycat,  by  Thijs  Kinkhorst
       <>,  for  the  Debian  system  (but  may  be used by

                                28 January 2005