2 Replies Latest reply: Mar 14, 2017 2:47 PM by vincent.on@bigpond.com RSS

RecoverPoint Vs MirrorView/SANCopy?


Why to buy additional appliance RecoverPoint as we already have MirrorView/SANCopy in place? what are the differences..

  • 1. Re: RecoverPoint Vs MirrorView/SANCopy?

    Hello Ravi,


    RecoverPoint is designed to produce high frequency snapshots of production data. By default, RP can create a crash-consistent local replica once per second, but this can be changed from its default setting to 'once per write I/O'. So, by default, every second we have a crash-consistent PIT image that we can recover from, if the need should arise. These high frequency snapshots are preserved in a private LUN pool called the Journal. The journal needs to be sized accordingly for both capacity and performance.


    Let's imagine that our database administrator discovers a d/b corruption at 10 am. If the Journal has been sized accordingly, we can recover from any previous crash-consistent PIT image that is present in the Journal (hence the Journal needs to be sized accordingly - read circular buffer here). Since, in my example, we have a detected corruption at 10am we could do the following:


    • <corruption detected at 10 am>
      • access the image from 9:30 am
        • IF 9:30 am image is corrupt
        • THEN
          • access the image from 9:15 am
          • ... repeat so as to continue to 'home-in' on that last good image
        • ELSE (9:30 image is good)
          • access the image from 9:45am
          • ... repeat so as to continue to 'home-in' on that last good image


    So, we can use a 'binary-chop' method to identify (and recover from) that last good image. (As a storage admin, the RTO may depend on our good working relationship with the d/b administrator).


    This small post cannot do justice to all the other benefits of RecoverPoint. Some of which are:


    • Heterogeneous support - RP supports both local and remote replication between heterogeneous arrays, including arrays from different vendors (but follow the support matrix, of course)
    • Intelligent GUI work flows for 'restores, from a local or remote replica, to production' and 'failover, from production, to a local or remote replica'
    • Optimized remote replication (compression, hot-spot detection, data de-duplication).
    • RP guarantees that all PIT images are 'crash-consistent' by preserving write-ordering across all volumes with a RP Consisteny Group.


    So, RecoverPoint micro-snapshots. If the Journal is sized accordingly, RP can preserve a crash-consistent PIT snapshot once-per-second for several days (or longer). However, important to remember here that RP is designed to mitigate against 'short-term' data loss and 'short-term' data corruption. Definition of short-term here will vary from customer to customer and data-set to data-set.


    One last point. In addition to the system generated micro-snapshots, you can also configure your own manual snapshots representing PITs of transactional consistency (eg. put database into hot backup mode, and then take a RP manual snapshot, or, unmount filesystem (sync buffer cache) take a RP manual snapshot). Both the system generated and manual snapshots are held in the Journal.


    Does this make sense?


    Thanks, Richard.

  • 2. Re: RecoverPoint Vs MirrorView/SANCopy?

    Hi Richard


    I have a customer who is wants to upgrade from the current CX-4 with MirrorView to VNX7600 with either MirrorView or RecoverPoint.


    The above information you have provided is about the RecoverPoint, could someone also explain the benefit, advantage of RecoverPoint over MirrorView on the VNX2? The PROD & DR are from HK to KL.


    Thank you in advance, Vincent