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F5_Freek_243545's avatar
F5_Freek_243545
Icon for Nimbostratus rankNimbostratus
Oct 05, 2016

TCP timeout issue

Hello Folks,

 

I'm going to ask a basic question..

 

Few applications (Lets say DB queries) getting time out issues. Between source and desitination, there is BIG IP forwarding VIP which is configured with 300s idle time out. The DB queries taking 10 mins to run and it is not returning any data because of this timeout issue.

 

we cant change this timeout value considering the number of connections. Is there any way specifically we can change this timeout value or a keep alive?

 

devops
LTM

5 Replies

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  • IainThomson85_1's avatar
    IainThomson85_1
    Icon for Cumulonimbus rankCumulonimbus
    Oct 05, 2016

    Why cant' you increase the value ? Is that based on evidence?

     

    The keepalive would be done to the application sending new Syn packets within the 300seconds.

     

  • Shaun_Simmons1's avatar
    Shaun_Simmons1
    Icon for Altostratus rankAltostratus
    Oct 05, 2016

    What type of DB server is it and what operating system? I have ran into this in the past...just curious.

     

  • ekaleido's avatar
    ekaleido
    Icon for Cirrus rankCirrus
    Oct 05, 2016

    Create a forwarding virtual specific to this type of traffic( ie, specify protocol and port, destination IP/subnet, etc), create a custom profile with longer timeout, apply new profile to new virtual.

     

  • F5_Freek_243545's avatar
    F5_Freek_243545
    Icon for Nimbostratus rankNimbostratus
    Oct 07, 2016

    Its Oracle DB.

     

    @Ian- nWe cant increase the timeout value which keeps open connections. In the past we have faced tmm memory issues due to the number of open connections for a period of time.

     

  • Jinshu's avatar
    Jinshu
    Icon for Cirrus rankCirrus
    Oct 07, 2016

    Use below irule. It does the trick. If the connecton is TCP and the port number is 1521 (Oracle DB port), it will change the idle timeout to 30 mins. Else it will go back to your fast l4 profile settings.

    when CLIENT_ACCEPTED { 
 if {[IP::protocol] == 6 && [TCP::local_port] == 1521} {
      IP::idle_timeout 1800
   }
 else {
      return
}
}

    -Jinshu