MTU 1990 invalid on gateway

[csurata]

Hi everyone, I’m getting notifications for my logins and I don’t know what the problem is: topics:radvd; warning; invalid mtu 1990 on ether1 from fe80::xx.

my settings

ipv6/nd print
Flags: X - disabled, I - invalid; * - default
0 * interface=bridge ra-interval=3m20s-10m ra-delay=3s mtu=unspecified
reachable-time=unspecified retransmit-interval=unspecified
ra-lifetime=30m ra-preference=medium hop-limit=unspecified
advertise-mac-address=yes advertise-dns=yes
managed-address-configuration=no other-configuration=no dns=“” pref64=“”


does anyone know how to resolve?

[rextended]

interface=bridge

What are the (L3) MTU of the bridge, the L2 MTU and (L3) MTU of ether1?

[csurata]

interface=bridge

What are the (L3) MTU of the bridge, the L2 MTU and (L3) MTU of ether1?

Hello;

nterface/bridge/print
Flags: X - disabled, R - running
0 R ;;; defconf
name="bridge" mtu=auto actual-mtu=1500 l2mtu=1568 arp=enabled
arp-timeout=auto mac-address=xx:xx:xx:xx:xx:xx protocol-mode=rstp
fast-forward=yes igmp-snooping=no auto-mac=no admin-mac=xx:xx:xx:xx:xx:xx
ageing-time=5m priority=0x8000 max-message-age=20s forward-delay=15s
transmit-hold-count=6 vlan-filtering=no dhcp-snooping=no

[csurata]

What are the (L3) MTU of the bridge, the L2 MTU and (L3) MTU of ether1?

Hello;

nterface/bridge/print
Flags: X - disabled, R - running
0 R ;;; defconf
name="bridge" mtu=auto actual-mtu=1500 l2mtu=1568 arp=enabled
arp-timeout=auto mac-address=xx:xx:xx:xx:xx:xx protocol-mode=rstp
fast-forward=yes igmp-snooping=no auto-mac=no admin-mac=xx:xx:xx:xx:xx:xx
ageing-time=5m priority=0x8000 max-message-age=20s forward-delay=15s
transmit-hold-count=6 vlan-filtering=no dhcp-snooping=no

[ interface/ethernet/print from=ether1 detail
Flags: X - disabled, R - running; S - slave
0 R name="ether1" default-name="ether1" mtu=1500 l2mtu=1568
mac-address=xx:xx:xx:xx:xx:xx orig-mac-address=xx:xx:xx:xx:xx:xx
arp=enabled arp-timeout=auto loop-protect=default loop-protect-status=off
loop-protect-send-interval=5s loop-protect-disable-time=5m
auto-negotiation=yes
advertise=10M-half,10M-full,100M-half,100M-full,1000M-half,1000M-full
tx-flow-control=off rx-flow-control=off bandwidth=unlimited/unlimited
switch=switch1 poe-out=auto-on poe-controller="gpio" poe-priority=10
poe-lldp-enabled=no power-cycle-ping-enabled=no power-cycle-interval=none


max L2 MTU = 9214

[csurata]

Anybody knows what’s happening?

[mkx]

topics:radvd; warning; invalid mtu 1990 on ether1 from fe80::xx.

It seems that there’s a router beyond ether1, which is sending out Router Advertisements and which include MTU size of 1990. I guess you could investigate a bit further to see which router is it.

[csurata]

topics:radvd; warning; invalid mtu 1990 on ether1 from fe80::xx.

It seems that there’s a router beyond ether1, which is sending out Router Advertisements and which include MTU size of 1990. I guess you could investigate a bit further to see which router is it.

Thank you,I disabled the RA of the router before the mikrotik