Greetings.
Models 951Ui-2HnD and 1100AHx2.
Running different versions of RouterOS from 6.42.7 to 6.48.6
I have found an issue with BGP on a lot of Mikrotik routers.
Mikrotik router on site is building GRE Tunnels with two border routers in Data-Center.
eBGP peering is established via this GRE Tunnels with each of two border routers in DC.
Two default routes are installed into routing table of Mikrotik router on site. Routes are received via eBGP.
Here how routing table does look like. One of two default routes is picked via "Lowest Router-ID BGP tiebreaker".
The issue is:
When GRE Tunnel 1, which leads to Border1 and from which bgp peer default route is "active", goes down second default route from Border2 does never become active. Even when first route from Border1 is withdrawn from routing table due to BGP peering is not "established" anymore and there is only one default route from Border2 leaft in routing table.
Default route from Border2 becomes active only if I disable and reanable Border2 bgp peer.
I tried to reproduce this issue in EVE NG lab, but had no success. All works as expected and bgp route is withdrawn quickly after GRE Tunnel falls.
Thanks in advance!