Cisco 2900 Switch flashing green and orange LED

[Gordon]

We have a Cisco 2900 XL Switch that is connected to a Series 4000
cisco router.

There are also a number of servers etc plugged into the switch.

All ports apart from the one from the router is in are green and flash
away as you would expect. However the port that the router goes into
is flashing steadily between green and orange at about 1/2 second
intervals. Switching the router to a different switch port does not
make a difference. The led's on the back of the router are all a
steady green.

Question is, what does a steady green/orange flashing LED actually
mean on the 2900 Catalyst switch? (cant find any reference to it on
cisco's site)

Thanks in advance.

[Jacek Woloszyk]

http://www.cisco.com/univercd/cc/td/doc/product/lan/c2900xl/c29xlmod/c29xlmi
g/mamotrb.htm
Port LED is alternating between green and amber.
Port is experiencing error frames. This could be due to a duplex
mismatch caused by autonegotiation, collisions, CRC errors, or alignment
errors.
Check the duplex settings on both devices. Check the speed settings on
both devices except when using a gigabit Ethernet module. You cannot change
the speed on the gigabit Ethernet modules. If one parameter is manually set,
manually set all of them, or set both devices to autonegotiate speed and
duplex. See the Catalyst 2900 Series XL Installation and Configuration Guide
for more information.

Hope that helps

Jack

Użytkownik "Gordon" <gordo...@totalise.co.uk> napisał w wiadomości
news:4979baaf.01082...@posting.google.com...

[Chris Jones]

Gordon,

I have a lot of 2900 XL switches at my site. I've found the 2900s
don't always autonegotiate correctly with certain types of devices. I
suggest manually setting the port speed and duplex on the 2900 and the
4000 to be the same and see if the problem goes away. I would suggest
starting off at 10 Mbps and half duplex. If that works bump up to 10 Mbps
and full duplex, then 100 and half and then 100 full.

FYI...

Chris

[Gordon]

Thanks for that web address, following a crash course in learning how
to configure the switch (There is nothing on the web interface that
says after clicking Apply, you have to copy the running config via the
command interface!), I've now got 2 ports configured to 10MB Half
Duplex, one for the router, and one for the hub, the servers are quite
happily talking 100/full on the other ports.

Anyway, the problems still continue, instead of green and orange all
the time, we now have green for about 10 seconds, then goes into the
green/orange routing for 5 seconds and then goes green again. I've
tried turning off both the switch and the router, turning the switch
back on, letting all the servers connect, then when everythings
stable, turning the router back on, same problem. Unfortunatly, I
cant get into the router as its part of a "BT Managed service"

I'm guessing that the most likely faulty component is the router as
everything else on the switch is working fine, but the router has
already had its ethernet port swapped out (could we have had a faulty
replacement?), or has anyone else seen some other part of the router
cause the ethernet port to pump out junk? Any ammo to blast at British
Telecom to get them to do some work for their money would be
appreciated.

Thanks again in advance.

[Lothar Hofmann]

Gordon wrote:
>
> Thanks for that web address, following a crash course in learning how
> to configure the switch (There is nothing on the web interface that
> says after clicking Apply, you have to copy the running config via the
> command interface!),

You don't have to use the command interface. You can save the
configuration
with the web interface by sytem->system-configuration->save
configuration.

I've now got 2 ports configured to 10MB Half
> Duplex, one for the router, and one for the hub, the servers are quite
> happily talking 100/full on the other ports.
>
> Anyway, the problems still continue, instead of green and orange all
> the time, we now have green for about 10 seconds, then goes into the
> green/orange routing for 5 seconds and then goes green again. I've
> tried turning off both the switch and the router, turning the switch
> back on, letting all the servers connect, then when everythings
> stable, turning the router back on, same problem. Unfortunatly, I
> cant get into the router as its part of a "BT Managed service"
>

Did you change the cable between router and switch? I had the
same problem (flashing green/orange with lots of bad packets)
and I solved it by replacing the patch cable.

Regards,
Lothar

Lothar Hofmann HRZ / computer center Mail:
hof...@star.hrz.uni-siegen.de
Universitaet Siegen
Hoelderlinstr. 3 Phone: +49 271 740 4760
D - 57068 Siegen Fax: +49 271 740 2523

[Terry Kennedy]

Gordon <gordo...@totalise.co.uk> writes:
> Anyway, the problems still continue, instead of green and orange all
> the time, we now have green for about 10 seconds, then goes into the
> green/orange routing for 5 seconds and then goes green again. I've
> tried turning off both the switch and the router, turning the switch
> back on, letting all the servers connect, then when everythings
> stable, turning the router back on, same problem. Unfortunatly, I
> cant get into the router as its part of a "BT Managed service"

Exactly what sub-model of 2900XL is it, and are the port number labels
(not the LEDs, but the acual numbers on the plastic) white, yellow, or
just molded into the plastic with no paint?

Non-VLAN-aware 2900XL's suffer from woefully inadequate port buffers.
This mostly shows up at 100Mbit/sec, but I've been able to reproduce it
at 10Mbit/sec in test cases.

I forget what the undocumented command is that shows the per-port
buffer drops.

In any event, if your port numbers aren't yellow, you have one of the
older, under-buffered models.

Terry Kennedy http://www.tmk.com
te...@tmk.com New York, NY USA