I have recently taken over the management of our companies WISP and am trying to resolve a strange issue. I am using a RB1100 to route Internet from our service provider to our WISP customers. Port 1 on the RB1100 is hooked to the Internet. Ports 2 - 10 route it to various sector AP's and backhauls. I have a couple of customers that have static IP addresses. At times they are unable to access the Internet. From the browser they get a page not found message. They run small business servers so their e-mail and website doesn't work when this problem occurs. Both users use MikroTik equipment for the CPE's. I can log into their CPE's but can't ping anywhere on the internet, using the /tools/ping command. I have tried rebooting the RB1100 and all the backhaul's, AP's and CPE's inline but that doesn't fix anything either. The strange thing is if I go into to the Radius server and give them a different static IP address, or if I change the username and password on their CPE to something different, the Internet starts working. Problem with doing this is that they need their static IP address to not change. I have run a trace route from their CPE when this happens and it seems to die at the RB1100. If we just wait some time it will eventually cure itself. This may be a few hours to a day or two. Waiting in unacceptable as they are not able to work while this problem occurs. Has anyone encountered this problem before? If so what did you do to fix it? Not sure what to do next. The RB1100 is running v5.26 as is the backhaul, AP and CPE involved. Let me know if I need to provide anything else to help troubleshoot this problem.

Thanks .. Jay

It sounds like there isn't anything wrong with the RB1100 and that its dropping packets on purpose for those IP's. Are there any firewall rules in place that are associated with those IP's?

i do have sometimes strange problems when i get double ip ranges from bgp .... then i need to add a bgp filter ...