Forum Discussion

A__N_5261's avatar
A__N_5261
Icon for Nimbostratus rankNimbostratus
Jan 16, 2013

ping showing LB Self Ip

Hi ,

 

Here is Scenario,

 

 

I have pool memeber 192.168.195.X and VIP is (192.168.166.100) ...... self ip on box is (192.168.195.1, 10.10.10.50.192.168.166.10)

 

 

all pool member default gateway pointing to 192.168.192.1

 

 

LB Route.. default gw 192.168.166.1

 

10.0.0.0 /8 10.10.10.3

 

 

There is not SNAT enable. just VIP and only one Pool member . simple config

 

 

My source is 10.66.66.100 from where i pinging. when i ping to VIP . I see reply coming from 10.10.10.50 (LB SELF IP) why ?

 

config
design

12 Replies

Sort By
  • A__N_5261's avatar
    A__N_5261
    Icon for Nimbostratus rankNimbostratus
    Jan 16, 2013
    can any body.. help on this. i don't know why it showing LB IP
  • Greg_33932's avatar
    Greg_33932
    Icon for Nimbostratus rankNimbostratus
    Jan 16, 2013

    I think your looking for X-forward to be ON so it shows the source IP. Create a profile and check the box. and add the profile to the VIP.

     

  • What_Lies_Bene1's avatar
    What_Lies_Bene1
    Icon for Cirrostratus rankCirrostratus
    Jan 16, 2013
    I'd assume the 10.10.10.50 address is the 'external' Self IP on the BIG-IP in the path between the client and server and that as the BIG-IP is proxying for that server, its providing that address? This would make sense unless you were routing on the BIG-IP.

     

     

    That or it's a bug. Anybody else?
  • A__N_5261's avatar
    A__N_5261
    Icon for Nimbostratus rankNimbostratus
    Jan 17, 2013
    Neo,

     

     

    No, I am not looking for X-Forward. the concern is only when ping to VIP . i see reply from Self IP.

     

     

     

     

     

     

  • A__N_5261's avatar
    A__N_5261
    Icon for Nimbostratus rankNimbostratus
    Jan 17, 2013
    Yes 10.10.10.50 is external self ip address between client and server .does it okey if asymmetric routing is happening ?
  • Stefan_Klotz's avatar
    Stefan_Klotz
    Icon for Cumulonimbus rankCumulonimbus
    Jan 17, 2013

    Hi,

     

    that's pretty easy, Ping towards a VIP will never be answered from the Poolmembers, but only from the VIP itself.

     

    And as the sourceIP of the Ping-request is unknown for your BIG-IP (not directly connected) it uses the configured route (10.10.10.0/8 -> 10.10.10.3) for the reply. To reach the next hop 10.10.10.3 it uses its own IP from that network, which is 10.10.10.50.

     

    So everything works correctly as designed ;)

     

     

    Ciao Stefan :)

     

  • What_Lies_Bene1's avatar
    What_Lies_Bene1
    Icon for Cirrostratus rankCirrostratus
    Jan 17, 2013
    Is asymmetric routing occurring? I've re-read your initial post and it suggests it is. Through the F5 on the way in to the server but not back from the server?
  • What_Lies_Bene1's avatar
    What_Lies_Bene1
    Icon for Cirrostratus rankCirrostratus
    Jan 17, 2013
    I also just realised you are pinging the VIP, for some reason I thought it was the Pool Member. That being the case I think this is expected behavior. The asymmetric routing doesn't come into it as you are pinging the VIP not the Pool Member.