Load Balancer port is connected to a switch and switch in turn connected to 3 servers in 3 VLANS(VlanX,VlanY,VlanZ).The port on the loadbalancer connected to switch is multinetted(hosting all 3 subnets of Servers and a tagged port which is member of all three VLANs). If a server in VLANX needs to ping server in VLANY then packet needs to come to loadbalancer(As LB is configured as the default gateway )and LB will route it to destination system which is in VLANY. My Doubt is What ever port the packet came on will be send out on the same port from load balancer as all macs of VLANX,VLANY and VLANZ were learned on same port.Is there any switching/routing rule that says ingress and egress needs to be on different port. Please clarify.Thanks asked 30 May '13, 15:15  krishnayeddula |
One Answer:
A switch won't normally forward packets out the same port as it ingressed. But only if the vlan ID is the same. In your case, you should look at the LB configuration. Some LB's (like F5 BigIP) will not forward traffic between vlans unless you set up it up yourself (forwarding virtuals on a F5 BigIP) answered 30 May '13, 15:47  SYN-bit ♦♦ |
Thanks Sake.In this case LB supports packet forwarding between vlans.Will this configuration valid if vlan forwarding is enabled on LB?
Yes, this is a very common setup. A LB one-armed connected with several vlans. You might want to consider bundling two ethernet interfaces for redundancy.