OSPF stops on l2tp interface

RouterOS General
1

i have
l2tp-server: routeros 2.9.46 (x86)
l2tp-client: routeros 3rc9 (rb333)

on sunday und today ospf stops working on the l2tp interface.
another rb532 with 2.9.46 and a l2tp tunnel to the l2tp server still works.
ospf between rb333 l2tp-client and another rb333 also works.

i can login through the l2tp tunnel to the rb333 l2tp-client and restart the board. after restart only this board everything works again.
is this a known problem?
what can i do to avoid this?
can i only restart ospf?

christian

2

i tested this again with a rb333.

the problem is the dsl reconnect. so the l2tp interface terminates and does not exist for a short time.

log says:
01:23:41 route,ospf,info OSPF neighbor 10.10.10.9: state change from Full to Down
01:23:49 l2tp,ppp,info l2tp-vpn: terminating… - session closed
01:23:49 l2tp,ppp,info l2tp-vpn: disconnected
01:23:49 l2tp,ppp,info l2tp-vpn: initializing…
01:23:49 l2tp,ppp,info l2tp-vpn: dialing…
01:23:49 l2tp,ppp,info l2tp-vpn: terminating… - old tunnel is not closed yet
01:23:49 l2tp,ppp,info l2tp-vpn: disconnected
01:23:49 route,ospf,error Join multicast group: IP_ADD_MEMBERSHIP failed
01:23:49 route,ospf,error interface=l2tp-vpn
01:23:49 route,ospf,error group=224.0.0.5
01:23:49 route,ospf,error error=No such device
01:23:49 route,ospf,error Cannot send packet: setsockopt IP_MULTICAST_IF failed
01:23:49 route,ospf,error ifindex=9
01:23:49 route,ospf,error error=Cannot assign requested address
01:23:49 l2tp,ppp,info l2tp-vpn: initializing…
01:23:49 l2tp,ppp,info l2tp-vpn: dialing…
01:23:50 l2tp,ppp,info l2tp-vpn: authenticated
01:23:50 l2tp,ppp,info l2tp-vpn: connected
01:23:50 l2tp,ppp,info l2tp-vpn: using encoding - MPPE128 stateless

here l2tp works again, but ospf does not come back.
only reboot helps?

Christian