Forum Discussion

pagema1_69881's avatar
pagema1_69881
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Mar 08, 2010

Very Slow Application performance behind F5

We have one application that performs very poorly behind F5. There is a 9 second delay on the initial GET request going through the VIP. If we bypass the F5 to the servers directly there is no delay...
config
design
L4L7_53191's avatar
L4L7_53191
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Mar 11, 2010
Maybe this then (source: wikipedia). Somehow having the VIP in line affected this process somehow and the lookups were breaking? An interesting bit of data may be to re-enable it on the NIC, then dump that UDP 137 traffic and see what is going on exactly in Wireshark (if you've not arlready done this). 

  
  In order to start sessions or distribute datagrams, an application must register its NetBIOS name 
  using the name service. NetBIOS names are 16 bytes in length and vary based on the particular 
  implementation. Frequently, the 16th byte is used to designate a "type" similar to the use of 
  ports in TCP/IP. In NBT, the name service operates on UDP port 137 (TCP port 137 can also be used,  
  but it is rarely if ever used).

-Matt