I've heard this concept a few times now. I'm not sure how only using OSPF for
the loopbacks works.
-----
Mike Hammett
Intelligent Computing Solutions
Midwest Internet Exchange
The Brothers WISP
----- Original Message -----
From: "Bruce Robertson" <br...@pooh.com>
To: af@afmug.com
Sent: Thursday, August 25, 2016 6:28:43 PM
Subject: Re: [AFMUG] Mikrotik OSPF weirdness
I've said it before, and been argued with... this is one of many reasons why
you use iBGP to distribute {customer, dynamic pool, server subnets, anything}
routes, and use OSPF *only* to distribute router loopback addresses.� All
your weird OSPF problems will go away.� My apologies if I'm misunderstanding
the problem, but my point still stands.
On 08/25/2016 10:22 AM, Robert Haas wrote:
Alright, this problem has raised it head again on my network since I started to
renumber some PPPoE pools.
Customer gets a new IP address via PPPoE x.x.x.208/32 (from x.x.x.192/27 pool).
Customer can�t surf and I can�t ping them from my office:
�
[office] � [Bernie Router] � [Braggcity Router] � [Ross Router] �
[Hayti Router] � [customer]
�
A traceroute from my office dies @ the Bernie router but I am not getting any
type of ICMP response from the Bernie router ie no ICMP Host Unreachable/Dest
unreachable etc � just blackholes after my office router.
A traceroute from the Customer to the office again dies at the Bernie router
with no type of response.
�
Checking the routing table on the Bernie router shows a valid route pointing to
the Braggcity router. It is also in the OSPF LSA�s.
--
Another customer gets x.x.x.207/32 and has no issue at all.
�
--
Force the original customer to a new ip address of x.x.x.205/32 and the service
starts working again.
�
--
�
Now � even though there is no valid route to x.x.x.208/32 in the routing
table � traffic destined to the x.x.x.208/32 IP is still getting blackholed..
I should be getting a Destination host unreachable from the Bernie router.
�
This is correct the correct response .206 is not being used and there is no
route to it:
C:\Users\netadmin>ping x.x.x.206
�
Pinging x.x.x.206 with 32 bytes of data:
Reply from y.y.y.1: Destination host unreachable.
Reply from y.y.y.1: Destination host unreachable.
�
Ping statistics for x.x.x.206:
��� Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
�
C:\Users\netadmin>tracert 74.91.65.206
�
Tracing route to host-x.x.x.206.bpsnetworks.com [x.x.x.206]
over a maximum of 30 hops:
�
� 1���� 6 ms���� 6 ms���� 7 ms� z.z.z.z
� 2���� 6 ms���� 6 ms���� 6 ms� y.bpsnetworks.com
[y.y.y.1]
� 3� y.bpsnetworks.com [y.y.y.1] �reports: Destination host unreachable.
�
Trace complete.
�
This is what I see to x.x.x.208 even though it is not being used and there is
no route to it.
C:\Users\netadmin>ping x.x.x.208
�
Pinging x.x.x.208 with 32 bytes of data:
Request timed out.
Request timed out.
�
Ping statistics for x.x.x.208:
��� Packets: Sent = 2, Received = 0, Lost = 2 (100% loss),
�
C:\Users\netadmin>tracert x.x.x.208
�
Tracing route to host-x.x.x.208.bpsnetworks.com [x.x.x.208]
over a maximum of 30 hops:
�
� 1���� 6 ms���� 6 ms���� 6 ms� z.z.z.z
� 2���� *������� *������� *����
Request timed out.
� 3���� *������� *���� ^C
�
--
�
I�ve verified there is no firewall that would affect the traffic � I even
put an accept rule in the forward chain for both the source and destination of
x.x.x.208 and neither increment at all. So the traffic is not even making out
of the routing flow and into the firewall..
�
Any pointers are where to start troubleshooting next?
!DSPAM:2,57bf295962076342819562!
