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MITUSER_21710's avatar
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Sep 13, 2011

F5 BIG IP LTM v10 does not follow the given virtual server order

We have created few virtual serves one forwarding virtual server with and a wildcard load-balancing virtual server with


The issue is traffic coming to on 80 is not matched to the forwarding virutal server and it is directly matched to wildcard virtual server.



Is this the normal behavior, if yes what we can do to match that specific traffic and froward to the destination rather than load-balanced by the wildcard virtual server


4 Replies

  • i think it should match how do u know it doesn't match?



    sol6459: Change in Behavior: Order of precedence for virtual server matching

  • Hi nitass



    I have read sol6459 earlier the issue is before v4 forwarding host had least priority, but after v9. they have not specifically mentioned the priority of the forwarding virtual servers.


    How we know is we see the packets on the wildcard virtual server pool when we do a tcpdump
  • sorry, you are correct.

    in my test, it hits wild virtual when telnet 80. will dig it further.

    [root@iris:Active] config  b virtual list
    virtual bar {
       translate address disable
       translate service disable
       ip forward
       snat automap
       ip protocol tcp
       profiles fastL4 {}
       vlans internal enable
    virtual wild {
       snat automap
       pool foo
       destination any:http
       ip protocol tcp
  • i did a little bit test and it appears traffic hits tcp virtual before fastl4 virtual server.


    [root@orchid:Active] config b virtual list


    virtual bar1 {


    ip forward


    destination any:any


    mask none




    virtual bar2 {


    destination any:any


    mask none


    ip protocol tcp




    [root@orchid:Active] config tcpdump -nni 0.0 port 80


    tcpdump: listening on 0.0


    18:23:38.020472 802.1Q vlan4094 P0 > S 3456383571:3456383571(0) win 5840 (DF) [tos 0x10]


    18:23:38.020513 802.1Q vlan4094 P0 > S 3948894867:3948894867(0) ack 3456383572 win 4380 (DF)


    18:23:38.020990 802.1Q vlan4094 P0 > . ack 1 win 1460 (DF) [tos 0x10]


    18:23:38.021045 802.1Q vlan4093 P0 > S 1391728281:1391728281(0) win 4380 (DF)