Veritas™ Resiliency Platform 2.2 Solutions for VMware
- Section I. Overview of Resiliency Platform
- Overview of Resiliency Platform
- Overview of Resiliency Platform Data Mover
- Overview of recovery to on-premises data center
- Managing assets protected by NetBackup
- Overview of Amazon Web Services
- Overview of vCloud
- Section II. Preparing your environment
- Using array-based replication
- Using Veritas Resiliency Platform Data Mover
- Managing disaster recovery network mapping
- Managing Replication Gateway pairs
- Using array-based replication
- Section III. Working with resiliency groups
- Managing resiliency groups
- Configuring resiliency groups for remote recovery
- Managing virtual machines for remote recovery (DR) using 3rd party replication technology
- Managing virtual machines for remote recovery (DR) using Resiliency Platform Data Mover
- Managing virtual machines for remote recovery (DR) in Amazon Web Services
- Managing resiliency groups
- Section IV. Managing disaster recovery
- Rehearsing DR operations to ensure DR readiness
- Performing disaster recovery operations
- Rehearsing DR operations to ensure DR readiness
- Managing resiliency plans
- Creating a new resiliency plan template
- Monitoring risks, reports, and activities
- Managing evacuation plans
- Appendix A. General troubleshooting
- Resolving the Admin Wait state
- Appendix B. Sample policy and trust relationships for AWS
How Veritas Resiliency Platform Data Mover handles virtual machine writes
Veritas Resiliency Platform Data Mover uses the vtstap service running on ESX host, to intercept and process protected virtual machine writes. The vtstap service intercepts the writes to the storage, while reads are directly processed from the virtual machine storage.
The vtstap service records the location of the write I/O, and also sequences the writes. The write is applied to the virtual machine storage and sequenced writes are then asynchronously sent to source replication gateway. The writes that accumulate on the source Replication Gateway are periodically sent to the target Replication Gateway. The target Replication Gateway applies the writes to the target data center storage in sequence. This ensures that data is consistent on the source and target data centers. As Resiliency Platform Data Mover employs asynchronous replication, there might be lag between source and target, but it will always be consistent.
Resiliency Platform Data Mover processes an incoming write by performing the following steps in the order listed:
The operating system in the guest VM issues a write to the virtual machine storage.
The I/O tap module (vtstap) records the location of the I/O.
IO is written to virtual machine storage.
The vtstap module sends the I/O data over the network to the I/O receiver in the source Replication Gateway.
The I/O receiver aggregates the I/Os.
Periodically, the aggregated I/Os are sent to the transceiver.
The transceiver sends the I/Os across the network to the transceiver on the target Replication Gateway.
The I/O is sent to the applier once the transceiver on the target replication gateway receives the set of I/Os.
The applier writes the I/O to the target data center storage.
The operating system in the guest VM issues a write to the virtual machine storage.
The I/O tap module (vtstap) records the location of the I/O.
IO is written to virtual machine storage.
The vtstap module sends the I/O data over the network to the I/O receiver in the source Replication Gateway.
The I/O receiver aggregates the I/Os.
Periodically, the aggregated I/Os are sent to the transceiver.
The transceiver sends the I/Os across the network to the transceiver on the target Replication Gateway.
The I/O is sent to the applier once the transceiver on the target replication gateway receives the set of I/Os.
The applier writes the I/O to the target data center storage.