Here is what my book says about the possible application of BGP
" The big motivation to use bgp occurs when you want to influence which link is used for certain destinations in the internet"
To make its point, author presents the following case:
The Caveat is
Traffic destined at 126.96.36.199 from company must use link 2
My argument is we can achieve the desired goal without using BGP.
For example ; ( option 1)
We statically create default routes on R1 and R2 pointing towards ISP and then redistribute them into Company's IGP
We will have ISP ( the company already owns 100.100.0.0/16 and this prefix length was not assigned by Company's isp) advertises this prefix via bgp on internet. ISP can create static route to 100.100.0.0 on its R1 and R2 pointing towards company's edges routers( R1 and R2)
we can create static route on R1 and R2 inside company as shown below
R1 ip route 188.8.131.52 0.0.0.0 s0/0 ( Link 2 )
R2 ip route 184.108.40.206 0.0.0.0 ss0/0 (link2)
Then we can redistribute this prefix on R2 into company IGP with a better metric.
We redistribute this prefix on R1 into company's igp with a higher metric than R1's.
The result all the traffic destined to 220.127.116.11 will be directed towards R2 which in turn sends them via link 2 to 18.104.22.168
We can achieve the same goal by using PBR on R2 and R1
We can configure a policy on all the interfaces that connect R1 to company's core network. We define the policy all the incoming traffic entering those interface and going to 22.214.171.124 will be forwarded to R1 as long as there is IP connectivity between R1 and R2's s0/0( because S0/0 on R2 connects to isp, we can use track command which will track SLA icm-echo operation between R1 and R2,s s0/0).
under normal conditions, all the traffic destined 1to 126.96.36.199 will be directed towards R2 which will forward them via link 2 .
If link2 goes down, the trackobject will go down on R1 which will stop all the traffic going to 188.8.131.52 from being forwarded to R2. All the traffic therefore will use link 1 via R1 to reach 184.108.40.206
My point is we can achieve the same goals without using BGP .So I am at lost so as to why the author of my book argues for using BGP in the above case.
Question We run asr9001 with XR 6.1.3, and we have a very long delay to
login w/ SSH 1 or 2 to the device compare to IOS device. After
investigation, the there is 1s delay between the client KEXDH_INIT and
the server (XR) KEXDH_REPLY. After debug ssh serv...
Introduction The purpose of this document is to demonstrate the Open
Shortest Path First (OSPF) behavior when the V-bit (Virtual-link bit) is
present in a non-backbone area. The V-bit is signaled in Type-1 LSA only
if the router is the endpoint of one or ...
Hi, I am seeing quite a few issues with patch install and wanted to
share my experience and workaround to this. Login to admin via CLI, then
access root with the “shell” command Issue “df –h” and you’ll probably
see the following directory full or nearly ...