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Ottimo_Massimo1's avatar
Ottimo_Massimo1
Icon for Nimbostratus rankNimbostratus
Jul 01, 2013

NAT configuration and Self IPs

Hi,

 

 

I guess this is a real LTM NAT 101 question, but it's been bugging me as it's the first time I've had to use NAT-specific configuration on the LTM.

 

We have some legacy configuration performing NAT like so:

 

nat "server internal IP" to "LTM external IP"

 

"server internal IP" is in LAN A 10.1.1.0

 

"LTM external IP" is in LAN B 182.168.1.1

 

 

My question is, presuming to are on separate LANs, does the LTM use it's self IP in relevant LANs (and if so, which self IP) to proxy traffic to the virtual machine? Therefore requiring the LTM to always have a self IP in both the server internal LAN and the external LAN?

 

 

Thanks!

 

config
design

1 Reply

  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Jul 06, 2013
    not sure if i understand question correctly. anyway, i do not think bigip uses selfip when nating.

    e.g. 

    root@ve10(Active)(tmos) list ltm nat
ltm nat 172.28.19.252 {
    originating-address 200.200.200.101
}

 telnet from external client (192.168.206.209) to nat ip (172.28.19.252)

root@ve10(Active)(tmos) show sys connection cs-server-port 23 all-properties
Sys::Connections
192.168.206.209:57522 - 172.28.19.252:23 - 200.200.200.101:23
-------------------------------------------------------------
  TMM           0
  Type          any
  Protocol      tcp
  Idle Time     1
  Idle Timeout  300
  Unit ID       1
  Lasthop       external 00:01:e8:d5:d4:47
  Virtual Path  172.28.19.252:23

                          ClientSide             ServerSide
  Client Addr  192.168.206.209:57522  192.168.206.209:57522
  Server Addr       172.28.19.252:23     200.200.200.101:23
  Bits In                        416                      0
  Bits Out                         0                    416
  Packets In                       1                      0
  Packets Out                      0                      1

Total records returned: 1