Discovery not working correctly

RouterOS General
1

Hi Guys,
i was testing 6.49.x and 7.10.x on an CRS317 and CRS326 both firmwares were not able to correctly display there neighbours.
Configuration:

  • Interface west and east transports vlans 2220-2229 and 2250 … VLAN 2250 is my Management-VLAN
  • Interface bridge1 vlan-filtering is turned on and the interface is configured with PVID on 2250

IP connectivity is working for IPv4 and IPv6.

But i can not see my neighbors. There is also something curious. The Discovery is configured on interface-list “discovery” but it shows a router on a interface that is not within that interface-list.


/ip neighbor discovery-settings
set discover-interface-list=discovery

/interface list
    add name=management
    add name=discovery
/interface list member
    add interface=bridge list=management
    add interface=bridge list=discovery
    
/interface bridge
    add auto-mac=yes name=bridge protocol-mode=none pvid=2250 vlan-filtering=yes
/interface bridge port
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=sfp-sfpplus9-rou ter
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=sfp-sfpplus10-router
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=sfp-sfpplus11-router
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=sfp-sfpplus12-router
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=bonding-west
    add bridge=bridge frame-types=admit-only-vlan-tagged interface=bonding-ost
/interface bridge vlan
    add bridge=bridge comment="BGP Access-Routers Network" tagged="sfp-sfpplus9-router,sfp-sfpplus10-router,sfp-sfpplus11-router,sfp-sfpplus12-router,bonding-west,bonding-ost" vlan-ids=2220-2221
    add bridge=bridge comment="Inband Management VLAN" tagged=bonding-west,bonding-ost,sfp-sfpplus9-router untagged=bridge vlan-ids=2250
    add bridge=bridge vlan-ids=2222
    add bridge=bridge vlan-ids=2223
    add bridge=bridge vlan-ids=2224
    add bridge=bridge vlan-ids=2225
    add bridge=bridge vlan-ids=2226
    add bridge=bridge vlan-ids=2227
    add bridge=bridge vlan-ids=2228
    add bridge=bridge tagged=bonding-ost,bonding-west vlan-ids=2229

This is the result of the neighbors list.

[rack@core-switch.130.de.pet.Lindlschmiedstr] > ip/neighbor/print
Columns: INTERFACE, ADDRESS, MAC-ADDRESS, IDENTITY, VERSION, BOARD
#  INTERFACE         ADDRESS      MAC-ADDRESS        IDENTITY                    VERSION                               BOARD             
0  sfp-sfpplus5-ost  172.16.10.4  08:55:31:56:0F:7A  router.de.tei.Rueckstetten  7.10.2 (stable) Jul/12/2023 09:45:11  CCR2004-1G-12S+2XS
   bonding-ost                                                                                                                           
   bridge
2

hello

from this guide,

https://wiki.mikrotik.com/wiki/Manual:IP/Neighbor_discovery

it said:

Summary
MikroTik Neighbor Discovery protocol (MNDP) and LLDP allows to “find” other devices compatible with MNDP or CDP (Cisco Discovery Protocol) or LLDP in Layer2 broadcast domain

ip connectivity is routed - hence not a single broadcast domain. so normally, you will not find any neighboring devices using layer 2 lldp.

There is also something curious. The Discovery is configured on interface-list “discovery” but it shows a router on a interface that is not within that interface-list.

the answer from above guide :

Since RouterOS v6.44 a neighbor discovery is working on individual slave interfaces. Whenever master interface (e.g. bonding or bridge) is included in the discovery interface list, all its slave interfaces will automatically participate in neighbor discovery. It is possible to allow neighbor discovery only to some slave interfaces. To do that, include the particular slave interface in the list and make sure that the master interface is not included.

hope this helps.

3

So from that point of view, i should:

  • Add a vlan-interface to bridge
  • Set type of bridge-vlan to TAGGED ONLY
  • Set PVID of bridge1 to 1
  • Add bridge1 to vlan as tagged port
  • Assign IP-Address to new added vlan-interface
  • replace interface-list for discovery with new added vlan-interface

hmmm… thats loony.