UPDATE! RB493G - problem with ETH reconnecting

RouterOS General
1

Hello, i have a problem with my new RB493G and i’m out of my own “guesses”, so hope someone help me here.

After first boot, i removed default configuration and set everything as i wanted. Everythig was fine until i plug the uplink cable. I have a WAN port set to Eth2 (because Eth1 is from the side, but all cables going behind the cabinet, so its easier to use another port). The main problem is, the WAN port going UP and DOWN over and over. This is part of the log:

18:24:34 interface,info 2_Uplink link down 
18:24:35 interface,info 2_Uplink link up (speed 100M, full duplex) 
18:24:36 interface,info 2_Uplink link down 
18:24:37 interface,info 2_Uplink link up (speed 100M, full duplex) 
18:24:38 interface,info 2_Uplink link down 
18:24:42 interface,info 2_Uplink link up (speed 100M, full duplex) 
18:24:44 interface,info 2_Uplink link down 
18:24:45 interface,info 2_Uplink link up (speed 100M, full duplex) 
18:24:48 interface,info 2_Uplink link down 
18:24:52 interface,info 2_Uplink link up (speed 100M, full duplex) 
18:24:57 interface,info 2_Uplink link down 
18:24:59 interface,info 2_Uplink link up (speed 100M, full duplex)

and over and over like this. I thought that i have somewhere some conflict, co i disabled all ports except WAN (Eth2), me (Eth3) and one more station (Eth6). To be sure, i disabled all NAT and FW rules and IGMP proxy. I keep active Bridge, DHCP client for WAN and DHCP server for the bridge. Unfortunately, still the same issue.

LAN connects:

Eth1 - nothing
Eth2 - WAN
Eth3 - Station (me)
Eth4 - Station (Off)
Eth5 - Station (Off)
Eth6 - Station (ON)
Eth7 - nothing
Eth8 - WiFi router (temporary, until miniPCI card arrive, also Off during the test)
Eth9 - NAS (Off)

Ports 3,4,5,6 are in BRIDGE

I was worried about the physical port can be broken, so to be sure, i changed the configuration. I set the Eth1 as WAN port and i added Eth2 to the existing bridge. Then i connect via Eth2. It was a supprise that everything was OK, no port up/down cycles, speed on 1000BaseT full duplex. But then, after few seconds, Eth6 (where another machine was conencted) start “cycling” in “UP/DOWN”.

So i start checking every configuration, because that was odd, and i found one possible cause of this problem in SWITCH setting.

NAME SWITCH VLAN-MODE VLAN-HEADER

0 1_Free > switch1 > fallback leave-as-is
1 2_WAN > switch2 > fallback leave-as-is
2 3_aaa > switch2 > fallback leave-as-is
3 4_bbb > switch2 > fallback leave-as-is
4 5_ccc > switch2 > fallback leave-as-is
5 6_ddd > switch1 > fallback leave-as-is
6 7_Free > switch1 > fallback leave-as-is
7 8_WRouter > switch1 > fallback leave-as-is
8 9_NAS > switch1 > fallback leave-as-is
9 switch1_cpu > switch1 > fallback leave-as-is
10 switch2_cpu > switch2 > fallback leave-as-is

Basicly, port which is on the same switch as WAN port failing, or the wan port failing.

I didn’t find any way how to turn off the switch, because i don’t need to use this (not now, maybe latter).

So can anyone please help me how to set things up to work properly? (I need keep the bridge set because of some FW/NAT rules.)

Thanks a LOT for any usefull info

BTW: I can set a guest account, if needed.

//EDIT: CPU overload solved.

2

you tried change the patch cord?

regards.

3

There is no problem with cables. If i put the same cable to another port, it is OK.

Like i said …
Uplink cable to Eth2 (set as WAN), workstation on Eth3 and Eth6 → problem on Eth2
Uplink cable to Eth1 (set as WAN), workstation on Eth3 (or Eth2, does not matter) and Eth6 → problem on Eth6

Cables are OK, but i’m missing something in configuration …

I’m trying to set up properly config for this, but i’m facing this stupid problem all the time on some port(s)…

1x WAN
4x workstation
1x NAS
1x WiFi router (temporary until miniPCI cart arrive)
1x Server
1x tunel - planned to next month

I need to have that workstations AND the NAS in one subnet. Since bridging is CPU consuming (and still does not working because of the port failing), i tried to set up a switch, but there is not enought port on one switch, because i need 5+1(as master) ← not possible. Server port plus tunel port will be isolated, about WiFi, it does not matter, its temporary.

I’m rly lost and tired now :confused:

EDIT: Ok, i finally understodt how those evil switches works … so my actual configuration is:

Eth1 - master port for Eth6,7,8,9(switch1)
Eth5 - WAN
Bridge - Eth1,2,3,4
DHCP server on Bridge

EDIT: I’m using RouterOS 5.5 and firmware is 2.29

4

Transferring data between a bridge and non-bridge port does use CPU depending on packet size and amount yes you can see 100% CPU

This is one of the reasons why we moved to using managed switches with RB’s hanging off a trunk port since it’s impossible to get a RB with more than 5 ports in the same switch group!!

5

Ok, thank you, so looks like i’ll buy some L2 8port switch and let Mikrotik only do the FW/NAT work + Wireless.

BTW: I still facing the port UP/DOWN “problem” … the connection on the end-point is not interrupted (like in prev. case), but still … what’s going on? It is HW failture and shoud i replace the RB or it is ROS bug and will be fixed? It does not happening when i had RG450G with ROS 4.9

03:47:29 interface,info 5_WAN link down 
03:47:30 igmp-proxy,info stopping IGMP proxy forwarding 
03:47:31 interface,info 5_WAN link up (speed 100M, full duplex) 
03:47:32 igmp-proxy,info starting IGMP proxy forwarding 
04:06:50 interface,info 7_Holy link down 
04:06:51 interface,info 1_Master link down 
04:06:52 interface,info 7_Holy link up (speed 100M, full duplex) 
04:06:53 interface,info 1_Master link up (speed 1000M, full duplex) 
04:42:15 interface,info 5_WAN link down 
04:42:16 interface,info 5_WAN link up (speed 100M, full duplex) 
04:42:16 igmp-proxy,info stopping IGMP proxy forwarding 
04:42:16 igmp-proxy,info starting IGMP proxy forwarding 
06:26:47 interface,info 5_WAN link down 
06:26:48 igmp-proxy,info stopping IGMP proxy forwarding 
06:26:49 interface,info 5_WAN link up (speed 100M, full duplex) 
06:26:50 igmp-proxy,info starting IGMP proxy forwarding 
11:56:47 interface,info 5_WAN link down 
11:56:48 igmp-proxy,info stopping IGMP proxy forwarding 
11:56:49 interface,info 5_WAN link up (speed 100M, full duplex) 
11:56:50 igmp-proxy,info starting IGMP proxy forwarding 
12:30:21 interface,info 7_Holy link down 
12:30:22 interface,info 1_Master link down 
12:30:24 interface,info 7_Holy link up (speed 1000M, full duplex) 
12:30:25 interface,info 1_Master link up (speed 1000M, full duplex)

(check prev post for information about ports)

Cables are absolutely OK (i checked them all yesterday with Fluke tester).

6

Updated my Mikrotik with Wireless card, so additional wifi router is not needed anymore, but i’m still having problems with the port falling…

Eth1 - master port for Eth6,7,8,9(switch1)
Eth5 - WAN
Bridge - Eth1,2,3,4,WLAN
DHCP server on Bridge



19:03:55 interface,info 6_test link down
19:03:59 interface,info 6_test link up (speed 1000M, full duplex)
19:07:50 interface,info 6_test link down
19:07:53 interface,info 6_test link up (speed 1000M, full duplex)
19:08:36 interface,info 6_test link down
19:08:40 interface,info 6_test link up (speed 1000M, full duplex)
19:10:29 interface,info 6_test link down
19:10:32 interface,info 6_test link up (speed 1000M, full duplex)

  • Cable is OK (on different port - OK, another cable - same problem)
  • Station is OK (tried the same workstation on another port - OK, another station on port 6 - same problem)

So, is this HW problem, or FW/SW problem? Or configuration problem / switch limitation ?

FW: 2.39
RouterOS: 5.14

7

Similar problem with the same RB (493G) Using 5.14, my Ethernet ports set at 1Gbps, connected to various different types of equipment, with Auto Negotiation - Turned on… Then sometimes when rebooting RB, dhcp cannot be passed to device, and winbox says the Ethernet port speed is 100mbps… ???

Has anyone seen similar issues? I have reloaded the FW, (latest) etc, and it works ok for a while, but after few reboots, things go a little haywire…

This RB is a vast improvement over the RB450G… But other issues, as such, are driving me crazy…

Like when I upgraded from 5.10-5.11/ and similarly again when upgrading 5.13-5.14 - was no simple process, it crashed after rebooting (to install upgrades) and I had to get in via serial cable… Yadda-yadda! ~ Oiii!

I’d be happy to send info to MK or anyone else if further details are required…

NO SOLUTION AS YET!!! Any work-arounds.. Or is this just an issue with v5.14?? And rb493G?

Cheeersssss…

Anthony@zeane.com

\

Cape Town - South Africa

8

Hello,

I experience the same problem. I’ve tested RouterOS 5.14 up to 5.25 and 6.0beta up to 6.1 with firmware 3.07 and earlier. WAN port is still going randomly up and down.
Here is the packet capture from today - 4 packets (all MAC & IP addresses were changed):

No.     Time               Source                Destination           Protocol Length Info
      1 08:16:59.842664000 <My_WAN_IP_ADDRESS>         255.255.255.255       MNDP     203    Source port: rrac  Destination port: rrac

Frame 1: 203 bytes on wire (1624 bits), 203 bytes captured (1624 bits) on interface 0
Ethernet II, Src: Routerbo_aa:04:37 (00:0c:42:aa:04:37), Dst: AsustekC_b2:27:cd (54:04:a6:b2:27:cd)
Internet Protocol Version 4, Src: 192.168.10.1 (192.168.10.1), Dst: 192.168.10.7 (192.168.10.7)
User Datagram Protocol, Src Port: 35554 (35554), Dst Port: 37008 (37008)
TZSP: Ethernet:
Ethernet II, Src: Routerbo_aa:04:33 (00:0c:42:aa:04:33), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: <My_WAN_IP_ADDRESS> (<My_WAN_IP_ADDRESS>), Dst: 255.255.255.255 (255.255.255.255)
User Datagram Protocol, Src Port: rrac (5678), Dst Port: rrac (5678)
Mikrotik Neighbor Discovery Protocol

No.     Time               Source                Destination           Protocol Length Info
      2 08:16:59.842665000 fe80::20c:42ff:feaa:443 ff02::1               MNDP     223    Source port: rrac  Destination port: rrac

Frame 2: 223 bytes on wire (1784 bits), 223 bytes captured (1784 bits) on interface 0
Ethernet II, Src: Routerbo_aa:04:37 (00:0c:42:aa:04:37), Dst: AsustekC_b2:27:cd (54:04:a6:b2:27:cd)
Internet Protocol Version 4, Src: 192.168.10.1 (192.168.10.1), Dst: 192.168.10.7 (192.168.10.7)
User Datagram Protocol, Src Port: 35554 (35554), Dst Port: 37008 (37008)
TZSP: Ethernet:
Ethernet II, Src: Routerbo_aa:04:33 (00:0c:42:aa:04:33), Dst: IPv6mcast_00:00:00:01 (33:33:00:00:00:01)
Internet Protocol Version 6, Src: fe80::20c:42ff:feaa:443 (fe80::20c:42ff:feaa:443), Dst: ff02::1 (ff02::1)
User Datagram Protocol, Src Port: rrac (5678), Dst Port: rrac (5678)
Mikrotik Neighbor Discovery Protocol

No.     Time               Source                Destination           Protocol Length Info
      3 08:16:59.842665000 Routerbo_aa:04:33     CDP/VTP/DTP/PAgP/UDLD CDP      142    Device ID: hq.hq  Port ID: wan

Frame 3: 142 bytes on wire (1136 bits), 142 bytes captured (1136 bits) on interface 0
Ethernet II, Src: Routerbo_aa:04:37 (00:0c:42:aa:04:37), Dst: AsustekC_b2:27:cd (54:04:a6:b2:27:cd)
Internet Protocol Version 4, Src: 192.168.10.1 (192.168.10.1), Dst: 192.168.10.7 (192.168.10.7)
User Datagram Protocol, Src Port: 35554 (35554), Dst Port: 37008 (37008)
TZSP: Ethernet:
IEEE 802.3 Ethernet
Logical-Link Control
Cisco Discovery Protocol

No.     Time               Source                Destination           Protocol Length Info
      4 08:16:59.842665000 Routerbo_aa:04:33     Broadcast             ARP      89     Who has <Provider_DHCP_SERVER>?  Tell <My_WAN_IP_ADDRESS>

Frame 4: 89 bytes on wire (712 bits), 89 bytes captured (712 bits) on interface 0
Ethernet II, Src: Routerbo_aa:04:37 (00:0c:42:aa:04:37), Dst: AsustekC_b2:27:cd (54:04:a6:b2:27:cd)
Internet Protocol Version 4, Src: 192.168.10.1 (192.168.10.1), Dst: 192.168.10.7 (192.168.10.7)
User Datagram Protocol, Src Port: 35554 (35554), Dst Port: 37008 (37008)
TZSP: Ethernet:
Ethernet II, Src: Routerbo_aa:04:33 (00:0c:42:aa:04:33), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Address Resolution Protocol (request)