bridge "A" is connecting all physical interfaces;
bridge "B" mainly for the wireless interfaces.
Thus, the L2MTU for bridge A and B can be managed separately.
However, this configuration is instable and sometimes crash the router and got rebooted. Here are some observations:
(i) After the reboot, a log "out of memory condition was detected" was displayed.
(ii) The CPU Profiler was done when the router was going to crazy, the process "SPI" consume 30% on one CPU core. The Disk utilization on all CPU also jumped to around 30 to 40%.
(iii) when the router hung, ping was not responding, winbox could not search it, webfig was not accessible. The only way to resolve this issue was to reboot the router manually.
(iv) the router hang even quicker if huge traffic is passing between bridge A to B.
The most strange behavior was the router didn't hang if I changed back the L2MTU of all physical interfaces from 9214 back to 1600 so that the L2MTU on Bridge A fell back to 1600.
Is there any known issue on this setup? if multiple bridges is not recommended, is there any other solution that can achieve the same goal?
Additional Information:
Configuration which is stable:
Code: Select all
/interface bridge> print
Flags: X - disabled, R - running
0 R name="B" mtu=auto actual-mtu=1500 l2mtu=1600 arp=enabled arp-timeout=auto protocol-mode=rstp fast-forward=yes igmp-snooping=no auto-mac=yes ageing-time=5m priority=0x8000 max-message-age=12s forward-delay=9s transmit-hold-count=6 vlan-filtering=yes ether-type=0x8100 pvid=1 frame-types=admit-all ingress-filtering=no dhcp-snooping=yes add-dhcp-option82=no
1 R name="A" mtu=auto actual-mtu=1500 l2mtu=1600 arp=enabled arp-timeout=auto protocol-mode=rstp fast-forward=yes igmp-snooping=no auto-mac=yes ageing-time=5m priority=0x8000 max-message-age=12s forward-delay=9s transmit-hold-count=6 vlan-filtering=yes ether-type=0x8100 pvid=1 frame-types=admit-all ingress-filtering=no dhcp-snooping=yes add-dhcp-option82=no
/interface ethernet> exp
/interface ethernet
set [ find default-name=ether2 ] l2mtu=1600
set [ find default-name=ether3 ] l2mtu=1600
set [ find default-name=ether4 ] l2mtu=1600
set [ find default-name=ether1 ] l2mtu=1600
set [ find default-name=ether5 ] l2mtu=1600
Code: Select all
/interface bridge> print
Flags: X - disabled, R - running
0 R name="B" mtu=auto actual-mtu=1500 l2mtu=1600 arp=enabled arp-timeout=auto protocol-mode=rstp fast-forward=yes igmp-snooping=no auto-mac=yes ageing-time=5m priority=0x8000 max-message-age=12s forward-delay=9s transmit-hold-count=6 vlan-filtering=yes ether-type=0x8100 pvid=1 frame-types=admit-all ingress-filtering=no dhcp-snooping=yes add-dhcp-option82=no
1 R name="A" mtu=auto actual-mtu=1500 l2mtu=9214 arp=enabled arp-timeout=auto protocol-mode=rstp fast-forward=yes igmp-snooping=no auto-mac=yes ageing-time=5m priority=0x8000 max-message-age=12s forward-delay=9s transmit-hold-count=6 vlan-filtering=yes ether-type=0x8100 pvid=1 frame-types=admit-all ingress-filtering=no dhcp-snooping=yes add-dhcp-option82=no
/interface ethernet> exp
/interface ethernet
set [ find default-name=ether2 ] l2mtu=9214
set [ find default-name=ether3 ] l2mtu=9214
set [ find default-name=ether4 ] l2mtu=9214
set [ find default-name=ether1 ] l2mtu=9214
set [ find default-name=ether5 ] l2mtu=9214