vradmin

NAME

vradmin - administer VERITAS Volume Replicator (VVR) in a distributed environment

SYNOPSIS

DESCRIPTION

The vradmin utility performs administrative tasks on a Replicated Data Set (RDS) in a VERITAS Volume Replicator (VVR) environment. Tasks available in vradmin include configuring, administering and displaying Replicated Data Sets, synchronizing remote volumes, and migrating or taking over the Primary role in the RDS.

A Replicated Data Set (RDS) is comprised of a Replicated Volume Group (RVG) on the Primary host and its counterparts on the Secondary hosts.

To perform an administrative task, vradmin accesses and changes the VVR configuration on the Primary and the Secondary hosts in an RDS.

The vradmin command can be executed from a Primary or any Secondary host in an RDS.

The vradmin keywords specify the operation to perform. Each operation can be performed on only one RDS at a time. The rvg argument is the name of a Replicated Volume Group (RVG) that specifies the RDS on the local host. Because the name of the Primary and Secondary RVG can be different, the same RDS can be represented by different names on different hosts.

The rvg or volume arguments determine a default local disk group, according to the standard disk group selection rules described in vxintro(1M). You can specify a local disk group using the -g diskgroup option.

KEYWORDS

addsec

Creates a Secondary RVG of the same name as the Primary RVG and adds it to the Replicated Data Set (RDS) rvg. The addsec command also associates existing data volumes and Storage Replicator Log (SRL) on the Secondary with the Secondary RVG. It creates and associates Primary and Secondary RLINKs (named rlk_sechost_rvg and rlk_prihost_rvg) with the Primary and Secondary RVGs.

The addsec command requires that the data volumes and SRL must exist on the Secondary with the same names and lengths as the data volumes and SRL on the Primary.

The arguments prihost and sechost specify the network connection to use for replication. They are resolvable names or IP addresses of the Primary and the Secondary host.

The addsec command can be executed from any host in the RDS. If an RDS contains only a Primary host, then addsec must be executed from the Primary host.

Caution: Do not execute the addsec command from the Secondary host that is being added to the RDS.

The Secondary can be created only if the /etc/vx/vras/.rdg file on the Secondary host contains an entry for the Primary disk group ID. Before creating the Secondary, this entry is validated as part of the addsec command. A plus character (+) entry in the /etc/vx/vras/.rdg file on the Secondary host allows addsec command for any disk group ID from any remote host to proceed.

The addsec command creates a Secondary RVG in the disk group with the same name as the Primary disk group. If required, you can use the option -sdg diskgroup to specify a different disk group on the Secondary.

If any of the data volumes or the SRL on the Secondary has Dirty Region Logs (DRL), the DRL is removed before the volume is associated with the Secondary RVG.

By default, the addsec command adds Data Change Maps (DCM) to the Primary and Secondary data volumes. Use the -nodcm option to specify that DCMs are not to be added to the data volumes. When the -nodcm option is used, the addsec command sets the srlprot attribute of the RLINKs to the value off instead of the default value of autodcm.

By default, the addsec command creates RLINKs named rlk_remotehost_rvgname. You can specify Primary and Secondary RLINK names using the prlink and srlink attributes. The expression to assign a value to an attribute takes the form attribute_name=value. For example, the following command creates Primary RLINK to_nyk and Secondary RLINK to_sfo, and adds Secondary nyk to RDS hr_rvg:

addvol

Adds an existing volume to the Replicated Data Set (RDS) rvg. This command associates an existing volume with the corresponding RVGs on all hosts in the RDS. The volume must have the same length on the Primary and Secondary hosts in the RDS.

If any of the Primary or Secondary data volumes that are to be added to the RDS have Dirty Region Logs (DRL), the addvol command removes the DRLs from these data volumes.

By default, the addvol command adds Data Change Maps (DCM) to the Primary and Secondary data volumes. Use the -nodcm option if you do not want to add DCM to the volumes.

If replication is in progress, make sure that the Secondary volume contains the same data as the Primary volume before adding the volume to the RDS. To transfer the data from the Primary volume to the Secondary volume over the network, use the vradmin syncvol command.

At the start of the addvol command, you are asked to confirm that the Primary and Secondary volumes contain the same data. Specifying the -s option skips this confirmation step.

changeip

Changes the network used for the replication between the Primary and Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed by the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The vradmin changeip command changes the hostname or IP address set in the Primary and Secondary RLINKs to the new values specified in the newpri and newsec attributes. These attributes are of the form attribute_name=value.

newpri

Specifies a new hostname or IP address for the Primary host that is to be used to establish a network connection for the replication to the Secondary. This is the new value for the local_host attribute of the Primary RLINK and the remote_host attribute of the corresponding Secondary RLINK.

newsec

Specifies a new hostname or IP address for the Secondary host that is to be used to establish a network connection for the replication. This is the new value for the remote_host attribute of the Primary RLINK and the local_host attribute of the Secondary RLINK.

Refer to vxedit(1M) for more information on the local_host and remote_host attributes of an RLINK.

createpri

Creates a Primary RVG rvg for the new Replicated Data Set (RDS) rvg. The volumelist argument is a comma-separated list of the existing data volumes. The srl argument is the existing volume that is to be used as the Storage Replicator Log (SRL) volume.

Before using the createpri command, use the vxassist or the vxmake command to create the data volumes and SRL with the required layout. Execute the createpri command on the host that is to be configured as the Primary host of the new RDS.

The createpri command starts the Primary RVG and then associates the data volumes and the SRL volume with the Primary RVG.

The createpri command removes the Dirty Region Logs (DRL) from the data volumes and the SRL volume if they have DRLs.

By default, the createpri command adds Data Change Maps (DCM) to the data volumes. Use the -nodcm option if you do not want to add DCM to the data volumes.

delpri

Deletes the Primary RVG (rvg), thereby deleting the corresponding Replicated Data Set (RDS) rvg. This command dissociates the data volumes and the SRL from the Primary RVG; it does not delete the data volumes and the SRL from the VERITAS Volume Manager configuration.

The delpri command fails if the Primary RVG to be deleted still has one or more Secondaries. Use the vradmin delsec command to delete all of its Secondaries before using the delpri command to delete the Primary RVG.

Use the -f option to delete a Primary RVG when the Primary data volumes are in use.

This command can be run only from the Primary host.

delsec

Deletes the Secondary sechost from the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed in the output of the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host. The delsec command dissociates the data volumes and the SRL from the Secondary RVG and deletes the Secondary RVG, the Secondary RLINK, and the Primary RLINK to the Secondary.

The delsec command fails if replication to the Secondary sechost is active. Use the vradmin stoprep command to stop replication to the Secondary.

delvol

Deletes the data volume volume from the Replicated Data Set (RDS) rvg. The delvol command dissociates the volume from the Primary and the Secondary RVGs in the RDS. The volumes are not physically deleted from the VxVM configuration.

Use the -f option to delete a volume from the RDS when the Primary RVG is not stopped.

fbsync

Converts a failed Primary to a Secondary in the Replicated Data Set (RDS) rvg. It also uses failback logging to synchronize data volumes on the failed Primary with the data volumes on the new Primary.

In failback logging mode, VVR uses Data Change Maps (DCM) to track the changes happening on the new Primary while the original Primary is not available. The fbsync command synchronizes the original Primary with the new changes on the new Primary by replaying the DCMs.

This method of failed Primary synchronization is recommended over the difference-based synchronization that is used by the syncrvg command. Failback logging neither requires all data blocks to be read, nor computation and comparison of checksums for the data blocks to be performed.

The fbsync keyword can optionally be used with the cache or cachesize attributes to create a space-optimized snapshot of the old Primary's data volumes before starting the resynchronization process.

The cache attribute specifies the name of an existing cache object.

The cachesize attribute specifies a default size for a new cache object with respect to the source volume.

All the snapshots are created on the cache object. The cache and cachesize attributes are mutually exclusive. If you do not specify either of these attributes, vradmin fbsync resynchronizes the original Primary's data volumes using DCM replay, without creating the snapshots.

The fbsync command returns immediately after starting the synchronization. Use the -wait option if you want the fbsync command to wait until the synchronization is complete.

ibc

Performs off-host processing task on the Secondary sechost in the Replicated Data Set (RDS) rvg using In-Band Control (IBC) Messaging. The argument sechost is the name of the Secondary host as displayed in the output of the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host. To perform the task on multiple Secondaries, specify a space-separated list of their names or IP addresses. Use the -all option to perform the task on all Secondaries in the RDS. The argument taskname identifies the off-host processing task and the corresponding user-defined scripts.

The vradmin ibc command uses IBC Messaging and executes a set of user-defined scripts to perform certain desired off-host processing task. See the VERITAS Volume Replicator Administrator's Guide for more information on In-Band Control Messaging.

The vradmin ibc command fails if the RLINKs are not in CONNECT state.

The vradmin ibc command executes the following user-defined scripts:

On the Primary host:

/etc/vx/vvr/ibc_scripts/<taskname>/quiesce /etc/vx/vvr/ibc_scripts/<taskname>/unquiesce

On the Secondary sechost host:

/etc/vx/vvr/ibc_scripts/<taskname>/prefreeze /etc/vx/vvr/ibc_scripts/<taskname>/onfreeze /etc/vx/vvr/ibc_scripts/<taskname>/postfreeze

The onfreeze script is mandatory. The vradmin ibc command fails if the onfreeze script does not exist on the Secondary host. The other scripts are optional. If the quiesce script is provided, the unquiesce script must also be provided and vice versa.

Below is a brief guideline on which operations should be implemented in each script:

quiesce

Quiesce the application running on the Primary data volumes and put the Primary data volumes in application-consistent state.

unquiesce

Unquiesce the application running on the Primary data volumes, that is, put the application back to the normal operating mode.

prefreeze

Perform operations needed on the Secondary RVG in preparation for the execution of the onfreeze script. For example, if the action in the onfreeze script is to take a snapshot of the Secondary data volumes, the prefreeze script can be used to add snapshot plexes to the Secondary data volumes.

onfreeze

Perform desired operation that requires the replication to be frozen on the Secondary RVG such as taking a snapshot of the Secondary data volumes.

postfreeze

Perform any necessary operations after the onfreeze script has completed and the replication on the Secondary RVG has resumed.

See the VERITAS Volume Replicator Administrator's Guide for detailed information on how these scripts work in the vradmin ibc command.

makesec

Converts a failed Primary to a Secondary of the new Primary in the Replicated Data Set (RDS) rvg. The argument prihost is the name of the new Primary host that was previously a Secondary of the failed Primary. The vradmin -l printrvg rvg command displays Primary-Primary configuration error if there are multiple Primary nodes in the Replicated Data Set (RDS) rvg. The prihost argument must be the host that is displayed with a Primary-Primary configuration error.

Use the makesec command to convert a failed Primary RVG to a Secondary in a failback procedure only if failback logging was not enabled during the takeover. To perform failback, first use the vradmin makesec command to convert the failed Primary to a Secondary. Then use the vradmin syncrvg command to synchronize the data volumes on the new Secondary (failed Primary) with the data volumes on the new Primary. Finally, at a scheduled time, use the vradmin migrate command to migrate the Primary role back to the failed Primary.

The -f option is used with the makesec keyword to convert a failed Primary to a Secondary, even when the Secondary data volumes are not up-to-date, or if any of the failed Primary data volumes are open.

migrate

Migrates the Primary role from the Primary host to a Secondary host in the Replicated Data Set (RDS) rvg. The Primary role can only be migrated when all the attached Primary RLINKs are up-to-date, consistent, and not in an error state. The data volumes in the RDS must be inactive, that is, applications involved in replication must be stopped before running the migrate command. After the migration completes, the former Secondary adopts the Primary role, and the former Primary adopts the Secondary role.

By default, the migrate command starts replication from the new Primary to the original Primary, which is now a Secondary. The command issues a warning if the replication does not start (that is, RLINKs do not change to CONNECT state). The migrate command also starts the RVG on the new Primary.

At the start of the migrate command, you are asked to confirm that all the applications using the Primary volumes have been stopped. You can use the -s option to skip this confirmation step.

pauserep

Pauses the replication to the Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed in the output of vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The pauserep command initiates a Primary pause that is independent of the host from which the command is executed. See the vxrlink(1M) manual page for more information on Primary pause and Secondary pause.

printrvg

Displays information about all RVGs in the Replicated Data Set (RDS) rvg. The host name, the RVG name, and the disk group are displayed for each RVG in the RDS starting with the Primary RVG. If the argument rvg is not specified, all Replicated Data Sets on the local host are displayed. Use the -g diskgroup option to display Replicated Data Sets in a particular disk group.

The -l option displays information in a long format. This format displays additional information such as number of data volumes, SRL name, and RLINK-related information for each RVG in the RDS. This option also displays configuration errors in the RDS, if there are any.

printvol

Displays information about data volumes in all RVGs in the Replicated Data Set (RDS) rvg. The host, disk group, RVG, and volume names are displayed for each RVG in the RDS starting with the Primary RVG. If the argument rvg is not specified, the above information is displayed for all Replicated Data Sets on the local host.

You can use the -g diskgroup option to display Replicated Data Sets in a particular disk group.

Information is displayed in a table format. The first column is the type field for each row. The second column contains information about the Primary RVG, if there is one. Information about the Secondary hosts is displayed in next columns. If there are more than two Secondary hosts in the RDS, information tables are repeated with the Primary in the second column.

The name, size (in blocks), plex count, and volume flags are displayed for each volume in the RDS. The printvol command is useful to view volume mappings between the Primary and the Secondary RVGs. Secondary volumes are displayed on the same row as the corresponding Primary volumes in the output. If a Primary or Secondary volume is not mapped, a dash (-) is displayed.

repstatus

Displays the current replication status of the Replicated Data Set (RDS) rvg. repstatus displays information about each RVG in the RDS starting with the Primary RVG.

Output of the repstatus command contains the following information for the Primary RVG: host name, RVG name, disk group, RVG state, number of data volumes being replicated, SRL name, SRL size, and the number of Secondary RVGs configured in the RDS.

For each Secondary RVG in the RDS, the following information displays: host name, RVG name, disk group, data status, replication status, current replication mode, and type of log currently in use. If the -l option is used, additional information such as RLINK names, replication mode configured in the RLINKs, latency protection setting, and SRL protection setting is also displayed for all the Secondary RVGs.

Following is a description of the important fields in the output of repstatus command:

RVG state

Indicates the state of the Primary RVG, for example, Primary RVG is currently enabled or disable for I/O.

Data status

Indicates whether the data on this Secondary is consistent or inconsistent with respect to the data on the Primary. If the Secondary is consistent, repstatus also displays whether the Secondary data is up-to-date, behind, or in stale state. A value of N/A indicates if the Secondary data needs recovery or its status cannot be determined (this may be due to a configuration error).

Current replication mode

Displays the current replication mode that is used to replicate data to the Secondary. This value can be different than the replication mode configured in the Primary RLINK if the replication mode configured is synchronous override.

Replication status

Indicates whether Primary data is being replicated to the Secondary. repstatus displays additional information in case data is not replicated.

Logging to

Displays whether updates to the Secondary are tracked using SRL or DCM. If the Secondary is not up-to-date, repstatus shows how far behind the Secondary is with respect to the Primary and the percentage of SRL used by this Secondary.

The repstatus command also displays configuration errors in the RDS, if there are any.

resizesrl

Increases the size of the Primary SRL in a Replicated Data Set (RDS) specified by rvg to the size specified by length. The size of the Primary SRL can be increased while the application is active or while replication is in progress. The resizesrl command does not increase the size of the Secondary SRLs in the RDS.

The resizesrl command increases the size of the Primary SRL only; it does not allow you to shrink the size of the Primary SRL.

The argument length is the desired size for the Primary SRL. The length can be specified using the standard length convention in VxVM. The argument length can be prefixed by a plus sign (+) to indicate an increase of the size of the Primary SRL by the specified amount.

resizevol

Resizes the data volume, volume, in a Replicated Data Set (RDS) rvg to the size specified by length. The resizevol command resizes the Primary data volume volume and the corresponding Secondary data volumes.

The argument length is the desired size for the data volume. The length can be specified using the standard length convention in VxVM. If the sizes of the Primary and Secondary data volumes are currently the same, the argument length can be prefixed by either plus (+) or minus (-) to indicate whether to increase or decrease the data volume size by the specified amount.

The resizevol command also resizes the file system on the Primary data volume as described in vxresize(1M).

If replication to any Secondary RVG is in progress, the resizevol command performs a secondary pause, resizes the volume, and then resumes the replication.

The -f option is required if any of the data volumes to be resized are being decreased in size.

If the resizevol command fails on any of the hosts in the RDS during its execution, the original volume sizes are not restored. This results in volume size mismatch between the Primary and its Secondaries. To correct this mismatch, re-issue the resizevol command with an absolute length.

resumerep

Resumes replication to the Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed in the output of the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The resumerep command resumes the Primary RLINK and the corresponding Secondary RLINK to resume replication. The command issues a warning if the replication does not resume (that is, RLINKs do not change to CONNECT state).

resync

Starts replay an active DCM in the Replicated Data Set (RDS) rvg.

The resync command starts replay of a DCM that is active due to SRL overflow or failback logging. Replay occurs for all RLINKs on which the dcm_logging flag is set. If any of these RLINKs are disconnected or paused, resynchronization is delayed until this condition clears. Detaching a disconnected or paused RLINK clears the dcm_logging flag, and allows resynchronization to proceed on any remaining RLINKs.

The resync keyword can optionally be used with the cache or cachesize attributes to to create a space-optimized snapshot of the secondary data volumes before starting the resynchronization process.

The cache attribute specifies the name of an existing cache object.

The cachesize attribute specifies a default size for a new cache object with respect to the source volume.

All the snapshots are created on the cache object. The cache and cachesize attributes are mutually exclusive. If you do not specify either of these attributes, vradmin resync resynchronizes the Secondary volumes using DCM replay, without creating the snapshots.

The resync command returns immediately after starting the synchronization. Use the -wait option if you want the command to wait until the synchronization is complete.

Refer to vxrvg(1M) for more information.

set

Changes the replication attributes for the replication to the Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed by the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The vradmin set command changes the replication attributes on both the Primary and Secondary. These attributes are of the form attribute_name=value.

The following attributes are available:

bandwidth_limit

Sets the maximum network bandwidth (in bits per second) that can be used during replication. The value may be qualified by the suffixes kbps or k for kilobits per second, mbps or m for megabits per second, and gbps or g for gigabits per second. The default value none removes the limit. The minimum allowed value is 56kbps.

latency_high_mark

Sets the maximum number of outstanding requests when latency protection is enabled.

latency_low_mark

After throttling is enabled, sets the level to which the number of outstanding requests must drop before throttling is disabled.

latencyprot

Indicates whether latency protection is enabled for the RLINK. The attribute may have one of following values: fail, off, or override.

Refer to vxedit(1M) for more information on these values.

packet_size

Sets the packet_size value. This is the number of bytes in a packet that is sent to a secondary RLINK.

protocol

Indicates the network transport protocol that is used by RLINKs for communicating between hosts. This attribute can take the value UDP for the UDP protocol, or TCP for the TCP protocol. The values TCP and UDP are case sensitive, and must be specified in upper case.

srlprot

Indicates whether log protection is enabled for the RLINK. Log protection prevents an RLINK from overflowing the SRL, which would cause it to become stale.

This attribute may have one of following values: autodcm, dcm, fail, off, or override.

Refer to vxedit(1M) for more information on these values.

synchronous

Indicates whether replication should operate in synchronous or asynchronous mode.

This attribute may have one of following values: off or override.

Refer to vxedit(1M) for more information on these values.

startrep

Starts replication to the Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed in the output of vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The startrep command attaches RLINKs on the Secondary and Primary to start replication.

The startrep command provides the -a, -c checkpoint and -f options. Only one of these options may be specified with this command.

The -a option starts autosync of the Secondary data volumes on command execution.

The -c checkpoint option attaches the Primary RLINK with the specified checkpoint.

The -f (force) option may be used if the Primary RVG is empty or if the Secondary data volumes contain the exact same data as Primary data volumes.

These options work in the same way as the corresponding options of the vxrlink att command (see vxrlink(1M)).

The startrep command issues a warning if the replication does not start (that is, RLINKs do not change to CONNECT state).

stoprep

Stops replication to the Secondary sechost in the Replicated Data Set (RDS) rvg. The argument sechost is the name of the Secondary host as displayed by the vradmin printrvg command. The argument sechost is optional if the RDS contains only one Secondary host.

The stoprep command stops the replication by detaching the RLINKs on the Primary and the Secondary host.

The stoprep command fails if the Secondary data volumes are not up-to-date with the Primary data volumes or if any of the Primary data volumes are open. Use the -f option to stop replication when the Secondary data volumes are not up-to-date or when any of the Primary data volumes are open.

On invoking the stoprep command, you are asked to confirm that you want to stop the replication. Stopping replication can result in the data on the Secondary volumes being out of date with respect to the Primary volumes. If replication is stopped, an autosync or difference-based synchronization of the Secondary volumes with the Primary volumes is required before replication can be restarted. You can use the -s option to skip this confirmation step.

syncrvg

Synchronizes or verifies data volumes on the host sechost in the Replicated Data Set (RDS) rvg with its Primary data volumes. The argument sechost is the name or IP address of the Secondary host as displayed in the output from vradmin printrvg. One or more Secondaries can be synchronized or verified at the same time by specifying a space-separated list of their names or IP addresses.

All volumes associated with Secondary RVGs are synchronized or verified with the corresponding Primary volumes. This is done by transferring the Primary volume data over the network.

There are two types of synchronization: full synchronization and difference-based synchronization.

In full synchronization, all data on Primary volumes is transferred to the corresponding Secondary volumes. Full synchronization is useful for creating the initial volume copies.

In difference-based synchronization, the difference between the Primary and the Secondary volume is first computed, and then only the blocks that are different are transferred to the Secondary volumes. The MD5 checksum is used to calculate the difference between the Primary and the Secondary data volumes. The MD5 checksum is generated using the MD5 Message-Digest Algorithm from RSA Data Security, Inc.

By default, syncrvg and syncvol use difference-based synchronization. Specify the -full option to perform full synchronization of the Secondary.

Before executing the syncrvg command to perform synchronization, use the vradmin stoprep command to stop replication to the Secondary, sechost.

Always use the -c checkpoint option during the RVG synchronization. When checkpoint is specified, the syncrvg command starts the checkpoint, performs the RVG synchronization, and stops the checkpoint when the synchronization is complete. After the RVG synchronization is complete, start replication by running the vradmin startrep command with the specified checkpoint.

Use the -verify option to verify and report the data differences between Primary data volumes and the corresponding Secondary data volumes. When used with -verify option, the syncrvg command only reports the differences between the Primary and Secondary data volumes; it does not synchronize the Secondary volumes with the Primary volumes. An MD5 checksum is used to calculate the difference between the Primary and the Secondary data volumes.

All applications using the Primary data volumes must be stopped (or quiesced) before running the syncrvg command with the -verify option. At the start of the -verify syncrvg command, you are asked to confirm that the Primary data volumes are not in use. You can use the -s option to skip this confirmation step.

If the bandwidth_limit attribute has been set for the RLINK, it is honored during this operation.

The syncrvg command reports the progress of synchronization or verification with the following column headings:

Eps_time

Total time that has elapsed (hh:mm:ss).

Dest_host

IP address of the host on which the current destination volume resides.

Src_vol

Source volume.

Dest_vol

Destination volume. (Data on the destination volume is synchronized or verified with data on the source volume.)

F'shed/Tot_sz

Amount synchronized or verified so far, and total size of the source volume.

Diff

Percentage of differences found. This percentage is relative to the total amount synchronized or verified so far. For full synchronization, this field is irrelevant and is displayed as "--".

Done

Percentage of the total size synchronized or verified so far.

syncvol

Synchronizes or verifies volumelist on remote host with volumelist on local host. volumelist is a comma-separated list of volume names. During synchronization, data on these local volumes is transferred to the remote host. host is the resolvable name or IP address of the remote host. The remote disk group and remote volume names are optional. When not specified, these names default to the same names as on the local host.

To synchronize or verify remote volumes with local volumes having different names, remote diskgroup and volumelist must be specified.

syncvol performs difference-based synchronization by default. To perform full synchronization, specify the -full option. See the syncrvg keyword for a description of sync options.

Remote volumes can be synchronized or verified with local volumes only if the /etc/vx/vras/.rdg file on the remote host has a local disk group ID entry in it. Before writing to or verifying with remote volumes, this entry is validated as part of the syncvol command. A plus character (+) entry in the /etc/vx/vras/.rdg file on a host allows syncvol command from any remote host to this host to proceed.

The -verify option is used to verify and report data differences between remote data volumes and the corresponding local data volumes. When used with the -verify option, the syncvol command only reports percentage data differences between remote and local volumes; it does not synchronize remote volumes with local volumes.

On invoking the syncvol command, you are asked to confirm that you want to overwrite data on volumes on the remote host with data from volumes on the local host (for synchronization), or that the local and remote volumes are not in use (for verification). You can use the -s option to skip this confirmation step.

You can use the bandwidth_limit attribute to specify the maximum network bandwidth to be used for this operation. See the description of set for an explanation of its usage.

See the description of syncrvg for an explanation of the output from this command.

takeover

Takes over the Primary role in the Replicated Data Set (RDS) rvg. The takeover command must be run from a Secondary host in the RDS. This command works only when the Primary host in the RDS is down or not reachable from the Secondary. The data on the Secondary must be consistent for takeover to work.

The takeover command is useful when the Primary host goes down due to an unscheduled problem or due to a disaster. During takeover the Secondary RVG is converted to a Primary RVG. Volumes associated with Secondary RVG are not accessible during takeover.

It is recommended that Secondary data volumes have Data Change Maps (DCM). This allows the takeover command to enable failback logging on the new Primary (or current Secondary). Once failback logging is enabled, the fbsync command can later be used to synchronize the data volumes on the failed Primary with the data volumes on new Primary.

The takeover command enables failback logging by default. The command fails if any of the data volumes on the Secondary do not have associated DCMs.

Use the -N option to convert Secondary to Primary without enabling failback logging. This requires either full synchronization or difference-based synchronization of the data volumes on failed Primary. Failback logging synchronization is the recommended method of synchronization. Refer to the fbsync command for more details.

To automatically synchronize the failed Primary once it becomes available, use the -autofb option with the takeover command. This converts the failed Primary to the Secondary once it comes up, and also uses failback logging to synchronize the data volumes on the failed Primary.

verifydata

Verifies the consistency of data between the Primary and Secondary hosts by creating space-optimized instant snapshots on the Primary and specified Secondary hosts. This command ensures that the snapshots are taken only after replication is frozen by using the vxibc commands. The main advantage of this command over the verify syncrvg command is that replication need not be stopped. Verification is possible, even when replication is in progress, because point-in-time snapshots are used for comparison.

The cache attribute specifies the name of an existing cache object.

The cachesize attribute specifies a default size for a new cache object with respect to the source volume.

All the snapshots for the volumes in the specified RVG are created on the cache object. The cache and cachesize attributes are mutually exclusive.

By default, this command destroys the snapshot volumes and the cache object after data verification has completed successfully.

To preserve the cache object, but not the snapshots that are configured on it, specify the -k cache option.

To preserve both the cache object and the snapshots, specify the -k snap option.

OPTIONS

-a

Starts replication with autosync. This option is used to attach the Primary RLINK as part of the startrep command.

-all

Performs the specified operation to all the Secondary hosts in the Replicated Data Set. This option can only be used with the ibc command.

-autofb

Automatically uses failback logging to convert and synchronize a failed Primary as soon as the failed Primary comes back up. This option can only be used with the takeover command.

-c checkpoint

Starts a checkpoint, transfers the data to remote host, and marks the checkpoint end, if specified with the syncrvg command. This checkpoint can be used to attach the Primary RLINK so that writes made to Primary volumes during synchronization are transferred to Secondary volumes.

This option can also be used with the startrep command to indicate the checkpoint to which the Primary RLINK needs to be attached.

-f

Forces an operation that is usually not allowed by vradmin.

When used with the delvol command, this option removes a volume from the RDS even when the Primary RVG is not stopped.

When used with the startrep command, this option starts replication by attaching the Primary RLINK with the -f option (as done by the vxrlink att command).

When used with the stoprep command, this option stops replication to a Secondary even when the Primary RLINK is not up-to-date.

When used with the delpri command, this option deletes a Primary RVG even when it has not been stopped.

When used with the resizevol command, this option allows shrinking a data volume size in an RDS.

When used with the makesec command, this option converts a failed Primary to a Secondary even if the Secondary data volumes are not up-to-date or any of the failed Primary data volumes are open.

-full

Performs full synchronization of volumes on local and remote hosts. This option works only with the syncrvg and syncvol commands.

-g diskgroup

Specifies the disk group for the operation, either by disk group ID or by disk group name. By default, the disk group is chosen based on the RDS rvg (if any).

-k cache

When used with the verifydata keyword, ensures that the cache objects are preserved after data verification has completed successfully.

This option cannot be used with the cachesize option.

-k snap

When used with the verifydata keyword, ensures that both the cache objects and the snapshots that are configured on them are preserved after data verification has completed successfully.

This option cannot be used with the cachesize option.

-l

When used with the printrvg command, this option displays RDS information in long format. In the long format, additional information such as data volume count, SRL name, and RLINK-related information are displayed for each RVG in the RDS. This option also displays any configuration errors in the RDS.

When used with the repstatus command, this option displays additional replication information such as Primary and Secondary RLINK names, replication mode configured, and settings for latency and SRL protection for each Secondary RVG in the RDS.

-N

Allows takeover without failback logging. This option can be used only with the takeover command.

-nodcm

Skip adding DCMs to data volumes. This option can be used with the addsec, addvol, and createpri commands.

-s

Works without prompting the user for confirmation. Specify this option to include the addvol, migrate, stoprep, [-verify] syncrvg and [-verify] syncvol commands in non-interactive shell scripts.

-sdg diskgroup

Specifies the disk group name on the Secondary host for the addsec operation.

-verify

Verifies and reports percentage differences between volumes on local and remote hosts. The volumes are not synchronized. This option works only with syncrvg and syncvol.

-wait

Blocks until synchronization is complete. This option can only be used with the fbsync and resync keywords.

FILES

/etc/vx/vras/.rdg

File containing disk group IDs for authentication in addsec and syncvol.

/etc/vx/vvr/ibc_scripts

Directory containing scripts used in ibc command.

/var/vx/vras/log

Directory containing log files for vradmind server.

EXIT CODES

The vradmin utility exits with a status of 1 if the attempted operation fails. This exit code is the same for all problems.

SEE ALSO

vxassist (1M), vxedit (1M), vxibc (1M), vxintro (1M), vxmake (1M), vxprint (1M), vxresize (1M), vxrlink (1M), vxrvg (1M), vxvol (1M)

VERITAS Volume Replicator Administrator's Guide