Something weird has started happening to me on multiple mikrotiks (2011SRM & 951) on multiple sites. Worst offenders are IP phones connecting to a cloud pbx via udp. Also found it happening with PC’s unable to connect to RDP and exchange.
Router is set up and everything works perfectly fine. Then suddenly a device (192.168.0.5/24 for demonstration purposes) starts getting timeout when it pings out over internet, but can access everything local. This applies to IP’s handed out by DHCP as well. Changing the IP of the device to say 192.158.0.6/24 will immediately let it work with no issues. Rebooting the switch also has no impact (some devices (in one case it is a on-premises PBX) are plugged into the MT directly). Normal stuff like SIP helper is off, and everything functions 100% until it starts not working. Rebooting MT doesn’t help either. If you then change the IP back to the previous IP it wont work, but if you give it a week or 2 then you can re-use the old IP and everything is fine.
Any advice?