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mherbst01
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RB800 Dropping Ethernet Link

Tue Apr 13, 2010 12:21 am

I just put up an RB800 + XR5, I've been noticing its dropping its ethernet link, Its being powered by pacwireles 48v PoE, its connected to a Cisco2950G. I have 3 other boards 433AH on that same switch and none are dropping, has anyone else seen this happen before? I did a /system routerboard settings print and got this..
baud-rate: 115200
boot-delay: 2s
boot-device: nand-if-fail-then-ethernet
enter-setup-on: any-key
cpu-frequency: 800MHz
memory-frequency: 400MHz
boot-protocol: bootp
enable-jumper-reset: yes
force-backup-booter: no

If that helps any, I'm bridging the wlan1 with the ether1 like I'm doing with all my other boards, one thing I noticed is under bridge the L2MTU is 2290, Ether1 is 1600. Anyways if anyone has any suggestions that I can check on the unit please, I will send a climber up the tower the min. I have clear sky's but I just want to rule anything out before I send someone up to re rerun cables and what not...
 
aaa
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 8:02 am

Try disable auto negotiation on RB800 and set speed to 100Mbit. What cable length you use?
 
poli5681
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 11:31 am

I have exactly the same setup; and of course the same problems. My RB800 is powered with POE (48V over datalines) and connected via 1Gbs link to a Cisco 3800.
Strangely our link is sometimes up for more than 12 hours and then suddenly drops and comes back seconds later.
I´ve disabled autoneg yesterday; Had no drops since then.
 
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janisk
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 11:51 am

just note that 1Gbps link requires auto-negotiation.
 
poli5681
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 12:28 pm

Thank you.

The link was up with 1Gbs and is now 100Mbit without autoneg and stable - didn´t see this.
The routerboards IF was set to 100Mbits but synced with 1Gbs. Does the speed setting do anything, when autoneg is enabled?
I´ll reenable autoneg, set the speed to 1Gbs (if that does anything) and wait...;
 
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janisk
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 12:35 pm

speed setting is ignored if auto-negotiation is set. It is there so you can set 100MBps or 10MBps if needed.
 
mherbst01
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 5:42 pm

Try disable auto negotiation on RB800 and set speed to 100Mbit. What cable length you use?
PoE cable length is probably 60ft max, jumper to switch 7ft, I tired taking it off auto negotiate and getting about 3% packet loss, gonna keep a ping going all day just to make sure it works. Before it would drop several times within an hr or two yesterday I lost it for about 30mins.
 
aaa
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Re: RB800 Dropping Ethernet Link

Tue Apr 13, 2010 10:03 pm

Try set 100Mbit half-duplex
 
mherbst01
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Re: RB800 Dropping Ethernet Link

Wed Apr 14, 2010 2:34 am

I set the device to 100/full and had it ping a device on the same switch 10000 times, dropped 2 packets. So it seems to have solved the issue, thank you everyone for your help.
 
mherbst01
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Re: RB800 Dropping Ethernet Link

Tue May 11, 2010 11:35 pm

I just recently revisted this issue, I am trying to set my Cisco switch to 100/full for the port going to the RB800, the RB800 is set 100/full as well auto negotiate off. The port however on the switch reads 100/half, so I set the port on the switch to 100/full and it drops connectivity to the rb800. It wont come back until I set it 100/auto, I really want this thing at 100/full.

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