On Wed, Mar 05, 2014 at 08:05:16PM +0000, Justin Marshall wrote: > Hi, > > We are having an OSPF issue. At least i'm assuming it's an OSPF issue > because there are no static routes involved. > > We have our core router (imagestream) connected via Fiber to a > Mikrotik at Tower A, Which in turn is connected via 2 RB411AH's with > Atheros AR922X's to a Mikrotik at Tower B. Every 500-1000 pings we > are loosing pings to 1 of the IP addresses on a bridge interface on > the Mikrotik at Tower B. When this happens I see an IP address that > is bound to one of the interfaces on our imagestream, show up on an > MTR like so... >
How is the wireless link from Tower A to Tower B configured? Are the RB411s bridged or do they participate in OSPF? How are the wireless AP and station interfaces configured? What is the OSPF interface configuration across the wireless link? Is the ImageStream up to date? Are you losing OSPF neighbor associations on the MikroTiks? Should show in the MikroTik log or you can just see how long the OSPF neighbor association has been installed. > Host Loss% Snt > Last Avg Best Wrst StDev > 1. 10.192.172.1 0.0% 3642 > 0.7 0.4 0.4 27.1 1.0 > 2. x.x.99.1 0.3% 3642 > 0.8 0.6 0.5 36.5 1.2 > 3. x.x.214.74 0.0% 3642 > 9.7 0.7 0.6 33.4 1.3 > x.x.36.209 > 4. x.x.214.66 0.0% 3642 > 8.0 10.3 0.7 75.1 9.1 > x.x.99.1 > 5. x.x.213.1 0.2% 3642 > 32.7 26.1 0.8 288.3 21.3 > x.x.36.209 > > > This is how it should look: > Host Loss% Snt > Last Avg Best Wrst StDev > 1. x.x.172.1 0.0% 4 > 0.8 0.9 0.5 1.4 0.4 > 2. x.x.99.1 0.0% 4 > 0.7 0.8 0.6 1.0 0.2 > 3. x.x.214.74 0.0% 4 > 1.2 1.1 0.7 1.7 0.4 > 4. x.x.214.66 0.0% 3 > 29.8 15.5 5.7 29.8 12.7 > 5. x.x.213.1 0.0% 3 > 15.3 14.4 13.8 15.3 0.8 > > > Both Mikrotik's are on 6.7, running OSPF. What we can't figure out > is why this x.x.36.209 keeps showing up in the route. While this is > happening, pings come back as: TTL exceeded. Also we aren't loosing > any pings to any other IP's on the Mikrotik in question at Tower B, > nor are we loosing pings to any other IP addresses bound to that > bridge interface. > > The IP that we are loosing pings to is a public IP vs the others being > private and not being in the /routing ospf networks. This may or may > not be relevant. There is also no NAT involved whatsoever. I may be interpreting your message incorrectly. Could you clarify if x.x.36.209 is an IP on an interface on the ImageStream? Or is it on a router at Tower C which may also be connected to Tower A via a wireless link? I suspect it is on the ImageStream. So, only the one subnet is falling out? At the time that you get looping traceroutes for 213.1, other subnets run clean? Are you only looping for the one IP in that subnet or for all hosts in the subnet? What does "show ip ospf route" look like from the ImageStream for anything in that /24? During the problem and while normal. What does "/ip route print where dst-address in x.x.213.0/24" look like on MikroTik A and B? Is x.x.213.1 the OSPF router ID of your MikroTik at Tower B? Have you made sure your all of your OSPF router IDs are all manually specified and unique within your network? Does the problem resolve itself after a bit? how long? or do you have to take some action to clear it? RouterOS 6.x has been better for us than 5.x for wierd OSPF issues. But it still seems a bit delicate. Especially if you have a misconfiguration somewhere or the wrong OSPF network type on a wireless bridge. -- Scott Lambert KC5MLE Unix SysAdmin [email protected] _______________________________________________ Mikrotik mailing list [email protected] http://mail.butchevans.com/mailman/listinfo/mikrotik Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
