OSPF Randomly Down Every 2-3 Days

RouterOS Forwarding Protocols
1

Hi,



I have this weird issue where OSPF goes down randomly every 2-3 days. The topology is very simple,

R1 (eth6) → L2 Provider Circuit → (eth7) R2



OSPF Interface Export :



R1:



/routing ospf interface

add interface=ether6 network-type=nbma



/routing ospf instance

set [ find default=yes ] distribute-default=if-installed-as-type-1 router-id=\

10.255.255.1



/routing ospf nbma-neighbor

add address=122.248.43.25





R2:

/routing ospf interface

add interface=ether7 network-type=nbma priority=0

add interface=vlan-102 network-type=broadcast passive=yes

add interface=vlan-101 network-type=broadcast passive=yes

add interface=vlan-104 network-type=broadcast passive=yes

add interface=vlan-105 network-type=broadcast passive=yes

add interface=vlan-106 network-type=broadcast passive=yes

add interface=vlan-107 network-type=broadcast passive=yes

add interface=vlan-108 network-type=broadcast passive=yes

add interface=vlan-109 network-type=broadcast passive=yes

add interface=vlan-110 network-type=broadcast passive=yes

add interface=vlan-111 network-type=broadcast passive=yes

add interface=vlan-112 network-type=broadcast passive=yes

add interface=vlan-114 network-type=broadcast passive=yes

add interface=vlan-103 network-type=broadcast passive=yes

add interface=ether2 network-type=broadcast passive=yes

add interface=ether5 network-type=broadcast passive=yes

add interface=ether6 network-type=broadcast passive=yes

add interface=vlan-6 network-type=broadcast passive=yes

add interface=ether1 network-type=broadcast passive=yes



/routing ospf instance

set [ find default=yes ] redistribute-static=as-type-1 router-id=10.255.255.2



/routing ospf nbma-neighbor

add address=122.248.43.254
priority=1





The log when OSPF is down is :



R1:

database Description packet has init bit set in middle of an exchange

OSPFv2 neighbor 10.255.2
5.2 : state change from Full to 2-way



R2:

OSPFv2 neighbor 10.255.255.1
: state change from Full to Down



R1 is currently running ROS 6.42.11

R2 is currently running ROS 6.42.9



I have set up a syslog server for R2 if you guys need more infos.



Thanks all!

2

No outages on the L2 circuit? Even briefly (a few seconds) that is long enough for a packet to disappear / be lost?

I’ve seen similar issues where one router would transmit a packet through a L2 provider circuit, and the packet doesn’t get to the remote side, causing OSPF to get confused.