What is SRDF group?
The SRDF group defines the logical relationship between SRDF devices and SRDF directors on both sides of the SRDF links. It is comprised of a range of SRDF devices and SRDF directors that reside on a given Symmetrix array.
What is SRDF split?
EMC SRDF logically pairs a device or a group of devices from each array and replicates data from one to the other synchronously or asynchronously. An established pair of devices can be split, so that separate hosts can access the same data independently (maybe for backup), and then resynchronized.
What is SRDF sync?
SRDF synchronous (SRDF/S)―SRDF/S replication maintains a real-time copy at arrays that are located within 200 kilometers. The local array immediately acknowledges writes from the production host, and, therefore, replication has no impact on host performance.
How does SRDF replication work?
SRDF logically pairs a device or a group of devices from each array and replicates data from one to the other synchronously or asynchronously. An established pair of devices can be split, so that separate hosts can access the same data independently (maybe for backup), and then be resynchronised.
What is SRDF Metro?
SRDF/Metro is a new feature available on the VMAX3/VMAX All Flash which provides active/active access to the R1 and R2 of an SRDF configuration. In traditional SRDF, R1 devices are Read/Write accessible while R2 devices are Read Only/ Write Disabled.
What is SRDF replication?
SRDF is basically a short form of Symmetrix Remote Data Facility. This is an intelligent software system for data replication from one Symmetrix Storage Array to another geographically distant location through a SAN or over an IP network.
What is SRDF failover?
EMC SRDF logically pairs a device or a group of devices from each array and replicates data from one to the other synchronously or asynchronously. During the SRDF failover operation the R1 devices are write-disabled, the SRDF link is set to Not-Ready (NR), then the R2 devices are write-enabled.
What is Unix SRDF?
How does SRDF Metro work?
But How Does it Work? Writes to the R1 or R2 devices are synchronously copied to the device’s pair. If a write conflict occurs, SRDF/Metro software resolves it to maintain consistent images on each of the SRDF pairs. The R2 device will assume all the traits of the R1 device including its geometry, device WWN, etc.
How do I set up SRDF?
How to Configure an EMC SRDF Replication Group
- Verify that the primary and secondary replicas are synchronized.
- Determine which node contains the primary replica and which node contains the secondary replica by using the symdg show command.
- Enable the secondary replica.
- Swap the RDF1 and RDF2 devices.
When to use the swap command in SRDF?
Swap command used in situations where we have to run the application from the DR site for a long time or to come back from an already DR running situation. It swaps the SRDF personality of the SRDF devices. Source R1 devices become target R2 devices, and target R2 devices become source R1 devices.
When does movepair enable consistency on SRDF / A?
Consistency on the SRDF/A group is not disabled when new devices are added with movepair (-cons_exempt). The same applies when suspending a device. The ENABLE you have seen may just be there for safety. I just tested the movepair to an SRDF/A group that was enabled and it stayed. The new device inherited the consistency enabled state.
Can a Symmetrix storage array be part of SRDF?
Symmetrix Storage arrays participating in SRDF can be parted away from few meters to thousand of kilometres connected through FC or IP network. SRDF solution can also be used for Data Migration from one Symmetrix array to another.
How does SRDF work in PowerHA SystemMirror?
Automatic failover and reintegration of server nodes that are attached to pairs of SRDF disk subsystems within sites and across sites. PowerHA SystemMirror supports SRDF replicated resources in synchronous mode (SDRF/S) and in asynchronous mode (SRDF/A).