HQ and 50 branches. HQ have 2 WAN link (ISP A & B) connected to Single 6500 Switch. Branches also have 2 WAN link
(ISP A & B) connected to single ISR router. Customer requirement is to have 2 tunnel from Branch to HQ and utilized both connection via PBR( Not loadbalancing)
Below is the illustration to create GRE tunnel
Branch WAN 1 (ISP A) ---> HQ WAN 1(ISP A)
Branch WAN 2 (ISP B) ---> HQ WAN 2(ISP B)
I planned to use DMVPN with OSPF. First of all, can I create 2 Tunnel in single Hub router instead of 2 Hub router each holding 1 single tunnel? If yes below is further questions.
If let say above setup is workable, i will make ISP A tunnel is Primary link and ISP B tunnel is secondary link by modifying OSPF cost in Tunnel interface. This because we dont need Load Balancing. And the major part is PBR. Customer request some traffic pass through ISP A tunnel and some traffic via ISP B tunnel, while the rest traffic which not specified in PBR should use ISP A tunnel failover to ISP B tunnel. This will be modified and time pass by. Now my question is;
when in branch I did PBR for specific traffic , In HQ i didnt do anything , just left OSPF routing, This will cause asymetric routing isn it? For eg, in Branch, traffic leave ISP B tunnel , reached HQ via ISP B tunnel, but exit HQ via ISP A tunnel(due to low OSPF cost in ISP A tunnel) and reach Branch via ISP A tunnel. Does this cause any problem? What if my branch router running Statefull Inspection firewall? How to overcome this?
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
[toc:faq]Introduction:This document describes details on how NAT-T
works.Background:ESP encrypts all critical information, encapsulating
the entire inner TCP/UDP datagram within an ESP header. ESP is an IP
protocol in the same sense that TCP and UDP are I...