Purpose

Starts, stops, or displays information about the Oracle ACFS replication background processes.

Syntax and Description

acfsutil repl bg -h
acfsutil repl bg {start | stop | info} [snap_shot@]mount_point

acfsutil repl bg -h displays help text and exits.

The following table contains the options available with the acfsutil repl bg command.

Oracle ACFS replication uses a background process on the primary cluster to transport file system changes to the standby location, either a file system or snapshot. This process must be running for replication to function. When replication is started with the acfsutil repl init command, the process is started and registered with Oracle Clusterware, enabling an automatic restart after a reboot or system crash. This process is clusterwide.

To determine if the Oracle ACFS replication background process is running at the primary site, you can run the acfsutil repl bg info command on the primary cluster. For examples of the use of the command, refer to Example 16-27.

Examples

Example 16-27 shows the use of the acfsutil repl bg command to display information about replication processes.

Purpose

Verifies that files have been replicated on an Oracle ACFS storage location.

Syntax and Description

acfsutil repl compare -h 
acfsutil repl compare [-v] [ -a [-s] | -t { all | tagname, ...} [-s] ]           
[snap_shot@]primary_mount_point [snap_shot@]standby_mount_point

acfsutil repl compare -h displays help text and exits.

The following table contains the options available with the acfsutil repl compare command.

The acfsutil repl compare command verifies all or part of the primary location has been replicated to the standby location. The standby location must be mounted locally for comparison. Best results are obtained when the primary location is changing as little as possible. The command always tries to check all files on the primary location against those on the standby location. To maximize the ability of the command to check all files, it should be invoked as the root user. However, this is not required -- the command will try to compare files when invoked as any user.

The -a option is typically used when no tag names were specified during the acfsutil repl init operation. The -a option compares all files on the primary location against those on the standby location. The -a option also enables tests for extra files on the standby location that do not exist on the primary. When testing for extra files, the command also attempts to check extended attributes. However, if NFS is used to mount the standby location locally, the standby cannot be checked for matching extended attributes due to limitations in the NFS protocol.

The -t option is used when tags were specified during the acfsutil repl init operation. The -t operation locates all file names on the primary location with the specified tag names and compares them to the corresponding files on the standby. The -t option takes as arguments either all option or a comma-delimited list of tag names. If the -t option is used with the all argument, then all tag names supplied during the acfsutil repl init operation are selected. Otherwise, any specified tag names must exactly match a tag name supplied during the acfsutil repl init operation. The -t option also tests for extra files on the standby location that do not have an associated tag name that was specified during the acfsutil repl init operation. If NFS is used to mount the standby location locally, the standby cannot be checked for matching tag names and extended attributes due to limitations in the NFS protocol.

You can use the acfsutil repl info -c option to determine which tags were specified during the acfsutil repl init operation.

The -a and -t options cannot both be specified at that same time. When -a or -t is provided, the —s option can also be specified to skip extended attribute comparisons for symlinks. If neither the -a nor -t option is provided, a primary to standby file comparison is done without testing tag names nor extended attributes.

The -v option may be specified to output the name of each file after the file is compared.

Examples

Example 16-28 shows the use of the acfsutil repl compare command.

Purpose

Displays information about replication processing on an Oracle ACFS storage location.

Syntax and Description

acfsutil repl info -h 

acfsutil repl info -c [-v] {[snap_shot@]mount_point}                    

acfsutil repl info -c -u user [-o sshStrictKey=yn_value] standby_host [standby_host...]
                    [snap_shot@]primary_mount_point

acfsutil repl info -c -u user [-o sshStrictKey=yn_value] primary_host [primary_host...]
                    [snap_shot@]standby_mount_point

acfsutil repl info -s [-v][-l] [-n number{m|h|d|w|y}] 
                   {-f eventlog | [snap_shot@]mount_point}}

acfsutil repl info [-a|-e|-t] [-v][-l]
                   {-f eventlog | [snap_shot@]mount_point }

acfsutil repl info -h displays help text and exits.

The following table contains the options available with the acfsutil repl info command.

To display information about replication configuration, use acfsutil repl info with the -c option. The configuration information includes a Applied primary as of timestamp that identifies the point in time on the primary location that the standby location represents. You can use this timestamp to set back a database to this point in time if it is necessary to keep the data in Oracle ACFS location synchronized with the database data replicated with Oracle Data Guard.

When specifying the -u option, the command should be run as repluser, the replication user. With this option, the command confirms that ssh, as used by snapshot-based replication, can connect from the local cluster to the remote cluster. The command should be used in two contexts:

• On each host of the primary cluster, to confirm that ssh can connect to all standby hosts and log in as user on each host

• On each host of the standby cluster, to confirm that ssh can connect to all primary hosts and log in as user on each host

When the command is run on a primary host, each standby_host string specifies a hostname or host IP address for a standby node. The specified [snap_shot@]primary_mount_point should be the active Oracle ACFS location in the primary cluster that is to be used for replication.

When the command is run on a standby host, each primary_host string specifies a hostname or host IP address for a primary node. The specified [snap_shot@]standby_mount_point should be the active Oracle ACFS location in the standby cluster that is to be used for replication.

In all cases, the user specified should be the same as the repluser specified in the acsfutil repl init command. If strict host-key checking was or is to be disabled for this instance of replication, for example with acsfutil repl init primary using -o sshStrictKey=no, then the option should also be specified here to skip host-key validation. acfsutil repl info -c -u can be run at any time, whether or not replication is currently active on the specified Oracle ACFS location.

To display information about replication statistics, use acfsutil repl info with the -s option.

To display information about all replication events, use acfsutil repl info with no options. To display information about a specific kind of event, use acfsutil repl info with the -a, -e, or -t option.

Examples

Example 16-30 shows the use of the acfsutil repl info command.

Purpose

Initiates replication on all the files in an Oracle ACFS storage location or only those files with a specified list of tags.

Syntax and Description

acfsutil repl init -h

acfsutil repl init standby -u repluser [-d trace_level] [snap_shot@]standby_mount_point

acfsutil repl init primary -s repluser@netname { -C | -M | -i interval} [tag_name...]
                           [-m [snap_shot@]standby_mount_point] [-d trace_level] [-z {on | off}] 
                           [-o sshCmdPath=pathname] [-o sshStrictKey=ynvalue] 
                           [-o sshCipher=ciphername] [-p repluser@netname] [-o sshOptions=options]
                           [-p [repluser@]netname] [snap_shot@]primary_mount_point

acfsutil repl init -h displays help text and exits.

The following table contains the options available with the acfsutil repl init command.

The acfsutil repl init primary and standby commands initiate replication between a specified primary site and a specified standby site. The acfsutil repl init standby command must be run first. Next, run the acfsutil repl init primary command.

When the acfsutil repl init primary command completes successfully, processing begins to replicate initial copies of all specified files to the standby location. In addition, any changes to these files and any new files subsequently created in the primary storage location are captured and transported to the standby location. However, successful completion of the command does not indicate that the specified files have been copied in full to the standby location. To monitor the progress of the initial replication of all specified files to the standby location, users can run the acfsutil repl info -c command.

The initial replication operation is based on a snapshot of the primary location, which is transferred to the standby location in its entirety. Each subsequent replication operation uses a later snapshot of the primary location, and only the differences between that snapshot and the last previous snapshot are transferred to the standby location.

All directories in the primary location are always replicated to the standby, even if tags are specified.

Symbolic link files are replicated as is. If the symbolic link resolves to an absolute path name, and that path name does not exist on the standby location, then referencing the symbolic link results in errors.

On platforms that support named sockets, character device files or block device files, these file types are not replicated.

The file system containing a primary or standby storage location can be mounted on only one mount point in its cluster. The file system does not have to be mounted on all of the nodes in a cluster, but if it is mounted, it must be mounted on the mount point specified with the acfsutil repl init command.  In addition, no other file system can be mounted on that mount point on other nodes.

A single Oracle ACFS location cannot be configured both as a primary and a standby location. If replication is configured on the same host or within the same cluster, then the primary and standby locations cannot use the same named mount point.

Replication is allowed between sites running any combination of the Linux, Solaris or AIX operating systems.

Examples

Example 16-31 shows the use of the acfsutil repl init to initiate snapshot-based replication from the primary to standby site.

Purpose

Pauses replication on an Oracle ACFS primary location.

Syntax and Description

acfsutil repl pause -h
acfsutil repl pause [snap_shot@]mount_point

acfsutil repl pause -h displays help text and exits.

The following table contains the options available with the acfsutil repl pause command.

The acfsutil repl pause command is issued at the primary replication site only. To continue replication operations, acfsutil repl resume should be run at a later time on the same primary site.

acfsutil repl pause stops the operation of the replication daemon temporarily. Subsequent running of acfsutil repl resume resumes the operation of the daemon.

If acfsutil repl pause is run while a replication operation is active, then the active replication operation completes regardless of the pause action. The pause operation is not effective in this case, and the command does not return, until the current data stream has been applied on the standby. After that, operations are not performed for this replication until the acfsutil repl resume is issued.

Examples

Example 16-32 shows the use of the acfsutil repl pause command.

Purpose

Resumes replication on an Oracle ACFS location where replication has been paused.

Syntax and Description

acfsutil repl resume -h
acfsutil repl resume [snap_shot@]mount_point

acfsutil repl resume -h displays help text and exits.

The following table contains the options available with the acfsutil repl resume command.

The acfsutil repl resume command resumes the replication process after the acfsutil repl pause command has been run. This command should be run on the same primary site soon after replication has been paused with the acfsutil repl pause command.

Examples

Example 16-33 shows the use of the acfsutil repl resume command.

Purpose

Synchronizes primary and standby locations.

Syntax and Description

acfsutil repl sync -h
acfsutil repl sync [apply] [snap_shot@]mount_point 

acfsutil repl sync -h displays help text and exits.

The following table contains the options available with the acfsutil repl sync command.

The acfsutil repl sync command can be used to synchronize the state of the primary site and the standby site. This command can only be run on the primary site. Users should first quiesce their applications and issue a sync(1) call to ensure that the synchronized state is known and meaningful to the user. Running acfsutil repl sync then ensures all outstanding replication data is shipped from the primary site to the standby site. Specifically, the command enables any in-progress replication operation to complete, and then performs replication one final time to ensure that all changes on the primary have been replicated.

The command completes successfully when all of the changes have been successfully applied to the replication location on the standby site. At this point, unless an unmount of the last node on the primary site cluster is about to occur, applications may be restarted.

Successfully unmounting a replicated location on the primary site does not guarantee that all changes made prior to the unmount have been successfully sent to the standby site or applied to the standby location. If the primary location is on a file system that is unmounted on one primary site node, but remains mounted on one or more primary site nodes, changes to the location made before the unmount continue to be transported to the standby site from the other nodes after the unmount. However, if you are in the process of unmounting the primary location on the last primary site node where it is mounted, and if you want to know that all file system changes on the primary location up to that point have been successfully applied to the standby location, then you should perform the following operations to ensure that the standby location is up to date.

• Quiesce applications on the primary site which modify the replication location.

• Run acfsutil repl sync.

After acfsutil repl sync has returned successfully, you can unmount the file system which contains the participating replication location. Unmounting the file system stops the replication background process for that location.

Examples

Example 16-35 shows the use of the acfsutil repl sync command.

Purpose

Stops all replication activity on the Oracle ACFS location at the site where it is run.

Syntax and Description

acfsutil repl terminate -h
acfsutil repl terminate primary [-d trace_level] [snap_shot@]mount_point 
acfsutil repl terminate standby [remote [-f]] [immediate] [-k] [-d trace_level] [snap_shot@]mount_point

acfsutil repl terminate -h displays help text and exits.

The following table contains the options available with the acfsutil repl terminate command.

The acfsutil repl terminate command stops all replication processing. When terminating replication, you should terminate replication for the primary location first, and then the standby location. If you want to ensure all changes are sent to the standby location before terminating the primary site, ensure that all applications are quiesced and run the acfsutil repl sync command. The terminate command must be run on both sites if both sites hosting the locations are available.

After acfsutil repl terminate standby has been run, you can use the standby location in read-write mode. If you want to restart replication after running acfsutil repl terminate, then you must restart replication from the beginning with the acfsutil repl init command.

The repl terminate standby command waits until replication data at the standby location has been applied. If you want to terminate replication immediately without applying all the replication data, use the immediate option. However, this option can leave some files at the standby location in an indeterminate state.

To momentarily stop Oracle ACFS replication, you can use the acfsutil repl pause command, followed soon after by the acfsutil repl resume command.

Examples

Example 16-36 shows the use of the acfsutil repl terminate command.

Purpose

Sets the replication trace level for gathering trace information on an Oracle ACFS location.

Syntax and Description

acfsutil repl trace -h
acfsutil repl trace level [snap_shot@]mount_point

acfsutil repl trace -h displays help text and exits.

The following table contains the options available with the acfsutil repl trace command.

Increasing the trace level can have a performance impact and should be done at the recommendation of Oracle support services.

Trace files for Oracle ACFS replication are stored in the following location:

GRID_BASE/diag/crs/hostname/crs/trace

In the location above, GRID_BASE specifies the ORACLE_BASE of the Oracle Grid Infrastructure home.

Examples

Example 16-37 shows the use of the acfsutil repl trace command.

Purpose

Updates replication information after replication has started and is running on an Oracle ACFS location.

Syntax and Description

acfsutil repl update -h

acfsutil repl update  [-s repluser@netname] [-C | -M | -i interval] 
                      [-d trace_level] [-z {on | off}] 
                      [-o sshCmdPath=pathname] [-o sshStrictKey=ynvalue] [-o sshCipher=ciphername]
                      [-p repluser@netname]
                      [-m [snap_shot@]standby_mount_point]
                      [snap_shot@]primary_mount_point
acfsutil repl update [-u repluser] [-d trace_level] [snap_shot@]standby_mount_point

acfsutil repl update -h displays help text and exits.

The following table contains the options available with the acfsutil repl update command.

The acfsutil repl update command updates replication information and configuration after replication has been started. For example, a system administrator can change the network interface that is currently being used by replication to connect to the remote site. Issuing the acfsutil repl update command to update the configuration in this situation enables replication to continue running uninterrupted.

If acfsutil repl update is run on the primary site, the command can be used to alter the user name and network interface name (hostname or VIP name) that is used to connect to the standby site as well as to alter the standby storage location.. The command can also be used to change the replication interval or tracing level, change the cipher used by or the pathname used for ssh, and turn compression on or off. Finally, the command can be used to update the network interface recorded for the primary site.

If acfsutil repl update is run on the standby site, the command can be used to alter either the tracing level or the user name used by the primary site to connect to the standby site.

At least one of the options must be specified when issuing this command; the command cannot be run with only the required location.

The acfsutil repl update command returns success when the updated information has been accepted on the local site. To change the user name, the command must be run on both the primary and the standby sites. If the replication interval is changed with the -C or -i option, a replication operation occurs at the point when acfsutil repl update is run. The next replication operation occurs based on the newly-specified interval.

Examples

Example 16-38 shows the use of the acfsutil repl update command.