Context-Aware Data Redundancy Elimination (DRE) ?

[johng231]

When is this going to be available? I came across it in an article which referenced available in v4.4. I'm running 4.4.1 and I don't see anywhere in the release notes about it. Perhaps it meant v4.5?

http://www.networkcomputing.com/wan-optimization-and-application-acceleration/231700318

[Bhavin Yadav · Accepted solution]

Hi John,

Yes this is available in WAAS v 4.4.1.

You will see it when you define policy on v4.4.1 box.

Here is the screen shot.

The condition here is - if the WAE running 4.4.x is in any Group and if the group has any WAEs running 4.1.x / 4.2.x / 4.3., you will not see this drop down menu with different directions and options. The WAE / Group should be running 4.4.x image in order to availa this feature.

You can find more details here:

http://www.cisco.com/en/US/prod/collateral/contnetw/ps5680/ps6870/prod_white_paper0900aecd8051d5b2.html

Above is a white paper and let us know if you can not access it.

Regards.

PS: Please mark this as Answered, if this Answers your question.

[johng231]

Thanks! This was the information I was looking for. Our default policy was set to bidirectional, after the upgrade. I'll have to wait until next year to change it to "Adaptive DRE" (Contex-Aware DRE feature). Hopefully, I'll start seeing the oldest dre data go up from days to weeks or maybe months.

This should work with all TCP application if we turn this feature on across all policies where it was set to bidirectional?

•  Bidirectional DRE: Data chunks and signatures are written to the disk  on both the sender- and receiver-side Cisco Wide Area Application  Engines (WAEs) to provide optimal compression.

•  Unidirectional DRE: Only signatures are written on the sender-side WAE,  and both signatures and data chunks are written the disk on the  receiver-side WAE. In addition to providing optimal compression, this  mode effectively uses the DRE cache for higher scalability.

•  Adaptive DRE: Context-Aware DRE intelligently chooses between the  bidirectional and unidirectional DRE caching mechanism depending on the  type of application traffic.

[Bhavin Yadav]

Yes, depending on your application configuration, it will work across all the connections thru that application.

Take care.

Regards.

[johng231]

I've enabled the Adaptive DRE setting this year across all TFO policies where bi-directional was enabled, after upgrading all of our WAAS appliances to version 4.4.1. We are getting complaints of network performance issues between lotus notes clients and the server. I went and changed the feature back to bi-directional for only the lotus notes policy.

I'm just wondering if anyone else had changed all bi-directional settings to the Adaptive DRE and are experiencing any network performance issues. Does anyone know if this not recommended for data base type applications?

So far I'm seeing a significant disk storage savings due to the Adaptive DRE setting, but I'm still only getting the oldest data age at 4 days on one of my core WAE-7371s. I was hoping this would improve it by at least a few weeks. I was thinking it would be more like a universal storage cache system. It looks like it still maintaining multiple context for each WAE peer.

show statistics dre detail

Cache:

    Status: Usable, Oldest Data (age): 4d17h

    Total usable disk size: 972787 MB,  Used: 94.82%

Cache details:

  Replaced(last hour): size  14165 MB

Cache write detail:

  Disk size saving due to unidirectional mode: 1006402 MB