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Help! Ethernet port stops responding on live border router!

Mon Jul 19, 2010 5:55 pm

I have two rb1000's.

One running ROS 3.30. Three months ago needed to connect my (200+ users) network to Cisco of ISP.
Could not make direct connect to Cisco box. Only with a bridged routerboard in between connection works fine. (This is already a very strange behaviour. Both of my two rb1000's DON'T want to ´speak´ with ISP's Cisco box. Any other router or laptop or PC has not a single problem speaking to the Cisco. While the same rb1000s have no problem ´speaking´ to any other device! Apart from the problem explained hereafter....)

After some weeks first rb1000 stopped working on WAN interface. All signs says "up and running" but only traffic going out, not in any more.... (I could log into LAN port, traffic still tried to run to WAN interface, but nothing comes back. Log shows nothing, Ethernet interface shows "up") Did a power cycle and board came up and went working like it should for days.... until after a week it happened again!
Replaced box for a rb1000 running ROSv5b2. Worked with same config for some weeks and then twice in a row stopped working on its LAN port with an interval of 3 days.!?! Yet again, all signs are ok (could log in via other interface) but only one way traffic. (Another connected router sends traffic but nothing comes back.)

Replaced this box for the original rb1000 with after a full factory default reset a new ROS v4.10. (with firmware upgrade!)
Unit ran for 5 days and today again just its LAN port stopped responding! I could not even log in via any of the other ports. :? :( Attached routers all say the link is ok. But only traffic TO the rb1000, no return traffic.

The only way to bring the port back alive is a simple power cycle. After that router starts up immediate and works like a charm.

Looked in the log. Nothing!
Looked in file list, no suppout.rif made. While watchdog is enabled!

Meaning, as far as the routerboard itself is concerned it has never been down at all! The only down is becuase I disconnected power... (and I don't think the router went down, the Ethernet port just stopped working.)

Has anyone seen the same behaviour?

I have seen similar behaviour on some lesser important routers in my network. Ethernet ports just stopped responding while other ports (ether + wireless) just kept on working. Login in these units via other ports didn't show anything special apart from the fact that the ill faithed port just is not receiving, but it is sending!
(Meaning that both adjacent routers are still sending to each other, but both don't see their opponents traffic any longer! And this on routers been working for days, cool environment, all earthed etc.!)
I even had some ports that stopped responding on IP level while I could still ping them with mac. But a mac telnet session was not possible.

This problem becomes really urgent becuase they are my main border routers to the internet.

Before both routers worked for 3 years in a row with ROS v2.xx without any problems ever...
Then these routers (for the fail-over setup) were connected on all interface to simple switches before they were connected to any other router...


On more remark: 1:1 src-nat from local (different networks) to public (one /24 network) also does not work without all IP addresses in use really mentioned in the interface! Proxy-arp enabled or disabled makes no difference! This morning found one public IP missing due an error of my side. I found out because client called me that after some weeks recess he could not use his internet. ARP-proxy still enabled. All I needed to do was to put the public assigned to him in the WAN interface and it worked.....
Don't know if this has anything to do with the problem described above....


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Re: Help! Ethernet port stops responding on live border rout

Thu Aug 26, 2010 7:14 am

I have the same problem right now. Call me 402-534-2502 ext 22.
Cell# 507-383-8012
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Dallas Weitzel
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Re: Help! Ethernet port stops responding on live border rout

Thu Mar 22, 2012 3:26 am

did u find the problem? got the same now on rb1000 i just stop working. but i have also problem to boot it up agian. it just hang do not get dobbel pip sound. in the lab i just plugd it in the power and after 2 hours i did get full bootup. but no errors.

Any one?
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Re: Help! Ethernet port stops responding on live border rout

Thu Mar 22, 2012 2:25 pm

Running on version 5 software and have no more problems. Also made sure all eq's are connected to earth.
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Rudy R. Puister

WISP operator based on MT routerboard & ROS.

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