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Revo_202489's avatar
Revo_202489
Icon for Nimbostratus rankNimbostratus
May 17, 2015
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Why does the BIG-IP create the connections for the UDP traffics?

Hi All,

 

I have been deployed a BIG-IP for the DNS server load balancing.

 

I knew that the connections for UDP traffic are on the BIG-IP.

 

The UDP protocol is stateless.

 

Why does the BIG-IP create the connections for the UDP traffics on the connection table?

 

Please explain why.

 

Thanks, Revo.

 

application delivery
LTM
management
monitor
  • asdfjkl_66468's avatar
    asdfjkl_66468
    May 17, 2015

    UDP is connectionless but it appears the LTM's will add some "statefulness" to a UDP connection. The info below is taken from Events For UDP Virtual Servers:

     

    "When the LTM receives a UDP datagram on a virtual server, it creates an entry in the connection table for that client IP and port (and, once a server has been selected, the server IP and port). As long as UDP traffic is flowing that matches that entry (either from the client to the server, or from the server to the client), it will all be considered a single connection."

     

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  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    May 17, 2015

    Why does the BIG-IP create the connections for the UDP traffics on the connection table?

     

    i might be wrong but if it does not, how does bigip send response back to the right sender?

     

  • asdfjkl_66468's avatar
    asdfjkl_66468
    Icon for Altostratus rankAltostratus
    May 17, 2015

    UDP is connectionless but it appears the LTM's will add some "statefulness" to a UDP connection. The info below is taken from Events For UDP Virtual Servers:

     

    "When the LTM receives a UDP datagram on a virtual server, it creates an entry in the connection table for that client IP and port (and, once a server has been selected, the server IP and port). As long as UDP traffic is flowing that matches that entry (either from the client to the server, or from the server to the client), it will all be considered a single connection."