VCB or Arcserve issue ?

I am setting vcb to use another directory to mount the vmware machines before backup, but its using the locating C:\Program Files\CA\ARCserve Backup Client Agent for Windows\VmwareVcbMountDir\

My config.js is the next, but the BACKUPROOT="E:
mnt" doesn t change to this directory.

What should I do ?


  • Generic configuration file for VMware Consolidated Backup (VCB).



  • Directory where all the VM backup jobs are supposed to reside in.

  • For each backup job, a directory with a unique name derived from the

  • backup type and the VM name will be created here.

  • If omitted, BACKUPROOT defaults to c:

  • Make sure this directory exists before attempting any VM backups.




  • URL that is used by "mountvm" to obtain the block list for a

  • disk image that is to be mounted on the backup proxy.


  • Specifying this option is mandatory. There is no default

  • value.




  • Port for communicating with all the VC SDK services.

  • Defaults to 443




  • Username/password used for authentication against the mountvm server.

  • VCB can be configured to use SSPI for authentication. The advantage

  • of using SSPI is that it does not require the password to be stored

  • in this configuration file in plain text. In order to be able to use

  • SSPI, the following conditions must be met:

  • 1) VCB must be configured to connect to a VirtualCenter Server

  • version 2.5 or newer and not to an ESX host directly. (i.e: "HOST"

  • must point to your VirtualCenter Server).

  • 2) VCB must always be used from a user context with the same username

  • and password credentials on both the proxy machine and the

  • VirtualCenter Server or be a domain user. The backup application

  • service process which calls VCB must be configured to run under

  • this user context. VCB and the backup application that calls it

  • must not be used in the Local System account context.

  • 3) The VCB user must have administrator privileges on the VCB proxy.

  • 4) The VCB user must be assigned to the "VCB Backup User" Role in

  • VirtualCenter.

  • If your setup meets all these conditions, you can enable SSPI

  • authentication by setting USERNAME to "__sspi__". The value for the

  • PASSWORD setting will be ignored in this case and hence can be set

  • to "".


  • As a third option, you can also specify the password using a Registry

  • key. The Virtual Machine Backup Guide has more information on this.


  • Specifying a user name is mandatory. For SSPI, the password needs to be

  • set, but is ignored. When specifying the password in the Registry, do

  • not set the PASSWORD variable here, since this will override the

  • Registry setting.





  • TRANSPORT_MODE determines how VCB accesses virtual disk data.

  • Currently, two modes are supported on Windows:


  • +) "san"

  • Virtual disk data is read directly off a shared storage device

  • that that the virtual disk resides on. This requires VMFS

  • storage on SAN or iSCSI and the storage device has to be

  • accessible from both ESX and the VCB proxy.

  • +) "nbd"

  • In this mode, VCB will use an over-the-network protocol to

  • access the virtual disk. Data is read from the storage device by

  • the ESX host and then sent across an unencrypted network channel

  • to the VCB proxy.

  • Please note that this mode does not provide the offload

  • capabilities of the "san" mode (since data is still transferred

  • from the ESX host across the network). However, "nbd" does not

  • require shared storage and also enables VCB to be run inside a

  • virtual machine.

  • +) "nbdssl"

  • This mode is same as "nbd" except that the data transfered over

  • the network is encrypted. The data transfer in "nbdssl" mode can

  • be slower and use more CPU than in the "nbd" transport mode. The

  • "nbdssl" mode will fail when connecting directly to ESX 3.0.x

  • or VC 2.0.x host.

  • +) "hotadd"

  • This mode is available only when using VCB in a VM. It allows the

  • data from the source VM to be backed up by hot adding its disks

  • to the backup VM. This gives the backup VM a very efficient data

  • access path to all the datastores accessible to the host running

  • the backing VM.


  • The default option is "san".




  • The log level determines the amount of log output generated by VCB.

  • Valid ranges are from 0 (least verbose) to 6 (most verbose), with a

  • default setting of 3. Change this setting to 6 when troubleshooting.




  • SNAPSHOT_POLICY determines how disk snapshots for backup are being created:

  • +) "automatic"

  • A snapshot is being generated automatically by the Interoperability

  • Module right before backup and it is being removed

  • automatically right after backup.

  • +) "manual" -

  • Exactly one snapshot named "_VCB-BACKUP_" must already exist for

  • each protected VM. The snapshot is mounted/unmounted on the proxy,

  • but the snapshot is neither created nor deleted by VCB.

  • This can be used to have external tools manage the backup snapshot.

  • +) "createonly"

  • The Interoperability Module will create the snapshot for each VM

  • right before it gets backed up, but will not remove the snapshot

  • after unmounting.

  • +) "deleteonly"

  • The Interoperability Module assumes that the snapshot named

  • "_VCB-BACKUP_" has been created beforehand. The snapshot will be

  • deleted automatically after backup.


  • The default option is "automatic"





  • The criteria to be used to identify a virtual machine


  • +) ipaddr

  • VMs are looked up based on their DNS name/IP address.

  • +) name

  • VMs are looked up based on their name as shown in VirtualCenter.

  • Note that backup will fail for VMs with non-unique names.


  • The default option is "ipaddr". You should only change this

  • if you have multiple sets of VMs with the same IP address, but with

  • different names.




  • Behavior for a backup job when the VM mount point already exists.

  • +) fail

  • A pre-existing mountpoint is causing a backup job to fail

  • +) delete

  • Attempt to remove the pre-existing mount point (and backup

  • snapshots associated with it). If this op. fails, fail

  • the backup job.


  • The default option is "fail"


  • Note that when TRANSPORT_MODE is set to "hotadd", the value for


  • the same, since it is not possible to reliably remmove a pre-existing

  • snapshot in this case without cleaning up the mount point.




  • Behavior for backup job when a previous backup snapshot of a virtual

  • machine already exists.


  • +) fail

  • A pre-existing backup snapshot is causing a backup job to fail

  • +) delete

  • Attempt to delete the pre-existing backup snapshot. If the

  • backup snapshot can be deleted without errors, proceed with

  • the backup job. Otherwise fail the backup job.


  • the default option is "fail"


  • Note that when TRANSPORT_MODE is set to "hotadd", the value for


  • the same, since it is not possible to reliably remmove a pre-existing

  • snapshot in this case without cleaning up the mount point.




  • Number of times an operation is re-tried after it fails.

  • You might want to use this option if you see a large number

  • of backup jobs fail with "resource busy" errors.


  • Usually, backup software will retry failed jobs, but it

  • might be hours until the backup software retries.


  • By default, retry is disabled (set to 0).




  • Number of seconds to wait before retrying a failed

  • operation. The default value is 10 seconds.


  • If you change this default, you probably also want to change

  • the default for MAX_RETRIES (since this setting only matters

  • if MAX_RETRIES is larger than 0).



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Arcserve is using the default mount path when VCB backup operations occur. You can specify the your a different mount path location by doing the following:

On the Backup Proxy System, Open the Registry Editor and navigate to the following key:

HKEY_LOCAL_MACHINE\SOFTWARE\ComputerAssociates\CA ARCserve Backup\ClientAgent\Parameters

Create a new String value and specify the following Value Name:


Modify the Value Data for the string so that it specifies the path where you want the agent to temporarily mount the VM during the backup operation as your example:


Run the Cstop.bat and then the Cstart.bat once the registry updates have been done.

Run a VCB job and it should now mount to the new location.

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