The Ciscos are receiving the default route via BGP from the upstream.
They are redistributing it to OSPF via "default-information originate".
No static defaults anywhere.
Craig
Quoting "can...@believewireless.net" <p...@believewireless.net>:
Are the Ciscos sending the default route via BGP or OSPF? If via BGP,
make sure you have Redistribute Default Route set in OSPF. Make sure
you don't have a static default route anywhere either.
On Fri, Dec 9, 2011 at 3:21 PM, Craig Baird <cr...@xpressweb.com> wrote:
I've got a very weird situation that has come up lately. Wondering if
anyone has any ideas. I've got two connections out to the Internet that
enter my network in two different locations. Upstream ISP is the same on
both connections. We run BGP with them via two Cisco edge routers. They
send us a default route, which I'm injecting into OSPF at both locations.
Now here's the weird part. If I lose BGP for connection A, every Mikrotik
V4 or V5 box in my network loses its default route completely. In contrast,
all my V3 or V2.9 (yes, I still have some of those) routers install the new
default route in the routing table, and off they go without so much as a
blink. If I do a 'routing ospf lsa print', the LSA for the new default is
there. But it never gets installed in the routing table. In order to get
these V4 and V5 routers to pick up the default, all I have to do is make a
change to OSPF somewhere on the network. I can make that change anywhere on
the network. It doesn't have to be on one of the V4 or V5 routers. Any
simple change will suddenly make these routers pick up the new default.
To make it even stranger, this problem doesn't happen in reverse. If I lose
BGP for connection B, the default route for connection A propagates to all
routers in the network and everything is fine.
I've been googling on this and found a few similar posts on the MT forum,
but nothing where MT has ever acknowledged that it's a bug. It sure looks
like one to me though, since it only affects V4 and V5 routers. I have a
difficult time believing that such a bug could exist through an entire
release's life cycle and well into the next without being fixed.
Does anyone have any insight on this?
Craig
_______________________________________________
Mikrotik mailing list
Mikrotik@mail.butchevans.com
http://www.butchevans.com/mailman/listinfo/mikrotik
Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
_______________________________________________
Mikrotik mailing list
Mikrotik@mail.butchevans.com
http://www.butchevans.com/mailman/listinfo/mikrotik
Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
_______________________________________________
Mikrotik mailing list
Mikrotik@mail.butchevans.com
http://www.butchevans.com/mailman/listinfo/mikrotik
Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
