Re: Advertising local host routes in BGP?

Using a 2811:

PSTN1(config)#int f 0/0
PSTN1(config-if)#ip add 192.168.1.241 255.255.0.0
PSTN1(config-if)#no shut
PSTN1(config-if)#
*May 6 20:47:20.373: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed
state to up
*May 6 20:47:21.373: %LINEPROTO-5-UPDOWN: Line protocol on Interface
FastEthernet0/0, changed state to up
PSTN1(config-if)#end
PSTN1#
*May 6 20:47:26.533: %SYS-5-CONFIG_I: Configured from console by console
PSTN1#
PSTN1#ping 192.168.0.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.0.1, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 1/1/4 ms
PSTN1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
PSTN1(config)#ip route 192.168.0.1 255.255.255.255 192.168.0.1
PSTN1(config)#end
PSTN1#ping 192.168.0.1
*May 6 20:48:19.337: %SYS-5-CONFIG_I: Configured from coconf t
PSTN1#ping 192.168.0.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.0.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
PSTN1#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
        D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
        N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
        E1 - OSPF external type 1, E2 - OSPF external type 2
        i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS
level-2
        ia - IS-IS inter area, * - candidate default, U - per-user
static route
        o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

      192.168.0.0/32 is subnetted, 1 subnets
S 192.168.0.1 [1/0] via 192.168.0.1
C 192.168.0.0/16 is directly connected, FastEthernet0/0

PSTN1#sh ip cef 192.168.0.1
192.168.0.1/32, version 10, epoch 0
0 packets, 0 bytes
   via 192.168.0.1, 0 dependencies, recursive
     unresolved
PSTN1#ping 192.168.0.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.0.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
PSTN1#sh ver
Cisco IOS Software, 2800 Software (C2800NM-ADVENTERPRISEK9_IVS-M),
Version 12.4(9)T7, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 10-Jan-08 16:36 by prod_rel_team
...

So it seems it's either architecture or IOS version dependent.

Jeffrey Pazahanick @ 6/5/2010 12:14 -0300 dixit:
> Carlos,
> What platform did you test a static route pointing to a host on a
> locally connected network?
> I'm labbing this on 1841s add get the following:
>
> R1(config)#do ping 1.1.1.5
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 1.1.1.5, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
> R1(config)#ip route 1.1.1.5 255.255.255.255 1.1.1.5
> R1(config)#do ping 1.1.1.5
> *May 6 15:14:52.925: RT: network 1.0.0.0 is now variably masked
> *May 6 15:14:52.925: RT: add 1.1.1.5/32 via 1.1.1.5, static metric [1/0]
> *May 6 15:14:52.925: RT: NET-RED 1.1.1.5/32
> *May 6 15:14:53.021: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> R1(config)#do ping 1.1.1.5
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 1.1.1.5, timeout is 2 seconds:
>
> *May 6 15:14:54.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:14:54.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop.
> *May 6 15:14:56.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:14:56.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:14:56.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop.
> *May 6 15:14:58.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:14:58.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:14:58.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop.
> *May 6 15:15:00.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:15:00.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:15:00.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop.
> *May 6 15:15:02.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:15:02.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop
> *May 6 15:15:02.677: RT: recursion error routing 1.1.1.5 - probable
> routing loop.
> Success rate is 0 percent (0/5)
>
>
> On Mon, Apr 26, 2010 at 3:32 PM, Carlos G Mendioroz <tron_at_huapi.ba.ar> wrote:
>> Have you been able to reproduce the issue in a lab environment ?
>> Because the statics pointing to the next hop should take care of the CEF
>> problem if I understood it...
>>
>> -Carlos
>>
>> Jeffrey Pazahanick @ 26/04/2010 17:28 -0300 dixit:
>>> The topology is like this:
>>>
>>> upstream peer upstream peer
>>> | |
>>> -------------------------------------------
>>> | |
>>> R1 (1.1.1.2) R2 (1.1.1.3)
>>> | g0/0 | g0/0
>>> -------------------------------------------
>>> |
>>> host (1.1.1.5)
>>>
>>> The issue I had was related to the CEF issue I mentioned when using
>>> static routes pointing to an interface, so I need find a different way
>>> of advertising host routes into BGP from a local network.
>>>
>>>
>>> On Thu, Apr 22, 2010 at 7:20 AM, Carlos G Mendioroz <tron_at_huapi.ba.ar> wrote:
>>>> Would you please repost your original topology and perceived problem ?
>>>> I got carried away because of your reference to the CEF issue, but
>>>> you have provided not enough info to actually reproduce your situation.
>>>>
>>>> -Carlos
>> --
>> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>>

-- 
Carlos G Mendioroz  <tron_at_huapi.ba.ar>  LW7 EQI  Argentina
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