Re: Advertising local host routes in BGP?

That is very interesting...

Anyone have an ASR1k running 2.5.2 laying around to test? :)

On Thu, May 6, 2010 at 3:39 PM, Carlos G Mendioroz <tron_at_huapi.ba.ar> wrote:
> 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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Received on Thu May 06 2010 - 15:53:18 ART