what is the required network speed in a snapmirror sync production environment?

[netappmagic]

I'd like to get a concensus advise on what the real network speed should be, in order to setup a snapmirror sync mode between two sites and in a real Oracle database production environment?

as i understand, sync mode requires low latency, and quick response from the remote site, otherwise, the performance on primary production will get effected. so, in your environment what is your network speed?

My additional question is, how Snapmirror can ensure the database consisitency? since when snapshot is being taken during the snapmirror, the database is still in write mode, not in a backup mode?

Thanks for your information!

[sawant]

In environment, What is your network speed or speed needed for SnapMirror Sync?

Since all of the data written to the source system must be replicated to the destination system as it is written, write throughput to the source system cannot generally exceed the bandwidth available between the source and destination system devices. It is important not to look at average write performance, but in order to avoid undesired performance impact, it is necessary to plan for the peaks in write performance.

In general, the configuration guideline is to configure the network between the source and destination system with two times the peak write throughput at the source system.

How can SnapMirror Sync ensure database consistency?

It does this by making sure that CPs are not written to disk until the writes are in NVRAM of the source and the destination filers. The storage does not acknowledge the write until the data has been written to both the source and destination systems. An example is below.

1. A user saves some information in the application.
2. The client software communicates with a server and transmits the information.
3. The server software processes the information and transmits it to the operating system on the server.
4. The operating system software sends the information to the storage.
5. The source storage sends the information to the destination system.
6. The destination system acknowledges receipt of the data.
7. The source system acknowledges receipt of the data.
8. The operating system tells the application server that the write is complete.
9. The application server tells the client that the write is complete.
10. The client software tells the user that the write is complete.

[netappmagic]

Thank you! It was very nice put