Forum Discussion

Piotr_Lewandows's avatar
Piotr_Lewandows
Icon for Altostratus rankAltostratus
May 09, 2016

Static routes and VLAN/Tunnel as Resource Type

Hi,   I was trying to figure out how VLAN/Tunnel type of static route is working. Looking at the GUI help as well as Routing docs I am still puzzled.   I would appreciate some real life example...
BIG-IP
devops
LTM
static route
vlan route
dragonflymr's avatar
dragonflymr
Icon for Cirrostratus rankCirrostratus
May 10, 2016

Hi,

 

Thanks a lot for answer. I hope I can understand it now but to be sure..

 

Scenario (Route definition):

 

  • Destination: 192.168.1.0/24
  • Resource: Use VLAN/Tunnel
  • VLAN/Tunnel: VLAN_X

Now there is a question how VLAN has to be defined:

 

  • Just VLAN assigned to given Interface
  • As above plus Self IP assigned to VLAN

Assuming that second option above is true, VLAN_X def is:

 

  • Self IP: 192.168.2.1/24

Having above def what will happen when packet with destination IP 192.168.1.1 is processed?

 

  • BIG-IP broadcast ARP request for 192.168.1.1
  • If there is any proxy ARP device that knows route to 192.168.1.1 it will answer with own MAC
  • BIG-IP will send packet with dst IP 192.168.1.1 and dst MAC of proxy ARP device
  • Proxy ARP device will send this packet using defined route either to destination host or to another upstream device

Is above correct?

 

I wonder what do you mean by "the BIG-IP would broadcast packets (L2 ff:ff:ff:ff:ff:ff) to the IP destination when the ARP goes unanswered" - packet will be send with dst IP 192.168.1.1 and broadcast MAC?

 

Piotr