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Brian_Gibson_30's avatar
Brian_Gibson_30
Icon for Nimbostratus rankNimbostratus
Jan 21, 2015

Dynamic TCP Tuning in 11.6

Hey folks,

 

So I am very interested in testing the TCP tuning features that supposedly came out in 11.6

 

According to the release it says they released the following feature...

 

Dynamic TCP tuning Modification of TCP profile parameters via iRules.

 

When I look at the IRule changes for 11.6

 

https://devcentral.f5.com/wiki/iRules.BIGIP_LTM_v11_6_0.ashx

 

I don't see anything that stands out as a guide to help learn what can and can't be done.

 

Does anyone have any information on this?

 

I see this...

 

DATAGRAM::tcp - returns tcp header information

 

But that appears to be just a retrieval command. It doesn't articulate what can and can't be changed or how.

 

application delivery
devops
iRules
LTM
performance

5 Replies

  • JRahm's avatar
    JRahm
    Icon for Admin rankAdmin
    Jan 23, 2015

    I'll do some digging and get back to you guys. Great question!

     

  • flupe_183924's avatar
    flupe_183924
    Icon for Nimbostratus rankNimbostratus
    Jan 23, 2015

    Hi all,

     

    Currently I am using radius accounting information to populate the access-type ...(LTE, UTRAN , WIFI..) From the tests that we're made, we did not have any "effect" of this dynamic feature in 11.6

     

    Flupe

     

  • JRahm's avatar
    JRahm
    Icon for Admin rankAdmin
    Jan 23, 2015

    Your lucky day, Brian. Turns out there are a ton of new TCP commands that came out in 11.6. I will get the wiki updated when I get the full documentation, but here's the list:

     

    • TCP::delayed_ack enable | disable
    • TCP::dsack enable | disable
    • TCP::abc enable | disable
    • TCP::pacing enable | disable
    • TCP::limxmit enable | disable
    • TCP::ecn enable | disable
    • TCP::idletime timeval
    • TCP::autowin enable | disable
    • TCP::congestion None | Reno | Newreno | HighSpeed | Scalable | Vegas | CDG | CHD | Illinois | Woodside | Cubic | Westwood+
    • TCP::lossfilter rate burst
    • TCP::sendbuf size
    • TCP::recvwnd size
    • TCP::proxybuffer high low
    • TCP::setmss mssval

    Looks like with all these settings, you can essentially create a procs library of "profiles" to switch programmatically base on your traffic analysis.

     

  • Stefan_Klotz's avatar
    Stefan_Klotz
    Icon for Cumulonimbus rankCumulonimbus
    Feb 01, 2017

    We are currently using the TCP::idletime in the iRule from the latest Exchange iApp-template (for Active Sync) and it doesn't seem to work correctly. Means the Connection will be dropped after 5 minutes, which is the Default TCP idle timeout. Once we increase this value directly in the VS-settings (clientside TCP-profile) everything is working fine.

     

    Did we make something wrong or are there any hints/ideas how to further analyze this issue?

     

    Thank you!

     

    Ciao Stefan :)