Steve,
Thx for checking this out. I received the same results last
evening in almost an identical config. Took me a few minutes to remember
the configure replace command so I did not have to boot everything in my
lab :)
My question is "how" one would see that split-horizon is being disabled
w/o it showing up in the sh ip int | in Split? I understand the absence
of routes tells you this indirectly, but shouldn't there be a way to see
it in a debug when eigrp is activated? I ran debug, but I did not see
anything relating to split-horizon being enabled. Maybe it is vaporware,
but you would think there is a way to see this besides the obvious
absence of routes.
Any ideas or is that just how it is? Either way, I just want to have it
nailed..
-R
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Di Bias, Steve
Sent: Monday, April 26, 2010 11:52 PM
To: [email protected]; Routt, Rob;
[email protected]; CCIE OSL
Subject: Re: [OSL | CCIE_RS] VOD Frame-relay
I just labbed this up with R2, R5, and R6, here are my findings. On the
hub (R2) I used a single physical interface (s0/0) and enabled RIP
advertising the 150.100.100.0/24 network, I did the same on R5 and R6.
Next I verified that split-horizon was disabled on the physical
interface
R2(config)#do sh ip int s0/0 | i Split
Split horizon is disabled
On R6 I created a new loopback interface using 6.6.6.6/32 and brought it
into the routing process, I'm now seeing the route on R5
R5#show ip route rip | i 6.6.6.6
R 6.6.6.6 [120/2] via 150.100.100.6, 00:00:13, Serial0/0
Next I enabled split horizon on R2's s0/0 and waited for it to timeout
on R5 (watching Deadliest Warrior during downtime :)
R2(config)#int s0/0
R2(config-if)#ip split-horizon
R2(config-if)#do sh ip int s0/0 | i Split
Split horizon is enabled
R5#sh ip route rip | i 6.6.6.6
R 6.6.6.6/32 is possibly down,
So by default split-horizon is disabled on physical frame relay
interfaces and RIP routes will be advertised.
What about EIGRP??
I'll use the same scenario by removing RIP and enabling EIGRP in AS 666
R2(config-if)#do sh ip int s0/0 | i Split
Split horizon is disabled
On R5 I never receive any D routes even though split-horizon is clearly
disabled on R2's s0/0
R5#sh ip ro
200.0.0.0/32 is subnetted, 1 subnets
C 200.0.0.5 is directly connected, Loopback0
150.100.0.0/24 is subnetted, 1 subnets
C 150.100.100.0 is directly connected, Serial0/0
Now let's disable split-horizon for EIGRP AS 666 on R2 s0/0
R2(config)#int s0/0
R2(config-if)#no ip split-horizon eigrp 666
R5#sh ip ro eig
D 6.0.0.0/8 [90/41152000] via 150.100.100.2, 00:00:09, Serial0/0
So For RIP split horizon is disabled by default on multipoint interfaces
(including the physical interface) but it is not disabled for EIGRP
unless you do it manually.
I hope this helps Rob :)
- Steve
-----Original Message-----
From: Joe Astorino [mailto:[email protected]]
Sent: Monday, April 26, 2010 4:04 PM
To: Di Bias, Steve; Routt, Rob; [email protected];
CCIE OSL
Subject: Re: [OSL | CCIE_RS] VOD Frame-relay
I would need to run a quick test to validate, but I do not recall split
horizon being disabled by default on physical interfaces at all
A good example would be trying to run RIP. I do not think you would get
spoke routes on the other spoke without disabling it
Sent from my Verizon Wireless BlackBerry
Regards,
Joe Astorino - CCIE #24347
Sr. Technical Instructor - IPexpert
Mailto: [email protected]
Telephone: +1.810.326.1444
Live Assistance, Please visit: www.ipexpert.com/chat
eFax: +1.810.454.0130
IPexpert is a premier provider of Self-Study Workbooks, Video on Demand,
Audio Tools, Online Hardware Rental and Classroom Training for the Cisco
CCIE (R&S, Voice, Security & Service Provider) certification(s) with
training locations throughout the United States, Europe, South Asia and
Australia. Be sure to visit our online communities at
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-----Original Message-----
From: "Di Bias, Steve" <[email protected]>
Date: Mon, 26 Apr 2010 18:46:41
To: Joe Astorino<[email protected]>; Routt,
Rob<[email protected]>;
[email protected]<[email protected]>
; CCIE OSL<[email protected]>
Subject: RE: [OSL | CCIE_RS] VOD Frame-relay
Joe is right; EIGRP will still be on by default under a physical frame
relay interface. You can use the "no ip split-horizon eigrp AS#" command
on the interface to disable.
Sorry about that
-Steve
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Joe Astorino
Sent: Monday, April 26, 2010 3:44 PM
To: Routt, Rob; [email protected]; CCIE OSL
Subject: Re: [OSL | CCIE_RS] VOD Frame-relay
You will still need to disable it for EIGRP specifically as well
Sent from my Verizon Wireless BlackBerry
Regards,
Joe Astorino - CCIE #24347
Sr. Technical Instructor - IPexpert
Mailto: [email protected]
Telephone: +1.810.326.1444
Live Assistance, Please visit: www.ipexpert.com/chat
eFax: +1.810.454.0130
IPexpert is a premier provider of Self-Study Workbooks, Video on Demand,
Audio Tools, Online Hardware Rental and Classroom Training for the Cisco
CCIE (R&S, Voice, Security & Service Provider) certification(s) with
training locations throughout the United States, Europe, South Asia and
Australia. Be sure to visit our online communities at
www.ipexpert.com/communities and our public website at www.ipexpert.com
-----Original Message-----
From: "Routt, Rob" <[email protected]>
Date: Mon, 26 Apr 2010 15:24:36
To: ccie_rs<[email protected]>
Subject: [OSL | CCIE_RS] VOD Frame-relay
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