Doorbird PoE intercom wont get IP address

[dastrix80]

Hi All

This device, run on POE works perfectly on an old switch/modem ive got at home.

As soon as I connect it into a switch module inside my Cisco 3945 (its the L3 24 port switch module) it wont get an IP from DHCP

I can see the switch port is up and I can see its MAC address on the switch module, but in the arp table on the router theres nothing.

Everything is in VLAN1. There is no configuration at all on the switch ports and all other devices work perfectly on the LAN

Any suggestions as to whats wrong?

I'm at a loss. The switch port shows orange as well, not green like the other devices. Looking into STP it goes from Listening to Learning, and back to listening...

Thanks!

[Reza Sharifi]

Hi,

The switch port shows orange as well, not green like the other devices.

Can you hard set the port to the correct speed and duplex and test again?

HTH

[Leo Laohoo]

Sounds like a cable problem. Is there a switch that can perform a TDR?

[dastrix80 · Accepted solution]

Changing the port to stp portfast fixed the issue... very odd!

[pieterh · Accepted solution]

this is really not odd. it depends on dhcp implementation on the client device.
if the dhcp process on the device reaches a timeout and stops dhcp request, you may encounter this behaviour
if the client repeats its dhcp-requests untill the port-handshake has fully completed then things may go well, but maybe take some time depending on the interval between requests.

for timing take into account:
- the client needs to negotiate the speed/duplex on the port
- the switch need to learn the mac adress
and determine using spanning-tree if it will open or block the port
- the switch may also need to determine if it will operate as trunk or access port

options to speed up port handshake
manually configure the port as access port
configure stp to accept/send packets for this port immidiately (portfast).
disable auto negotiation of speed and duplex on both the switch and the device
disable auto mdi/mdi-x between switch and device (implicit on switch when disabling auto speed/dup)
use the right cable (straight, not crossed) between device and switch

[dastrix80]

Thanks, port fast was the solution :)

[Loki1986]

I've got the same problem...
Port looks like its going down all the time. Even when there is no configuration. 
Im a complete N00b for this (years ago that I've been busy with configurating switches)

How can I solve this problem? I don't get an IP.

This picture below gives a "simulation" about the wired connections. Connected directly to the modem/router, there isn't a problem. Connected to a cysco catalyst 2960 or 3560, he doesn't get an IP.

With what (even commands, really to long ago) command can i fix it? (if I can fix it now, i can go configuring more by myself)

[Leo Laohoo]

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@Loki1986 wrote:

years ago that I've been busy with configurating switches

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Is this for school work that you're posting?
I don't believe you've configured Cisco switches before.

Will you take ownership and responsibility that IF/when your instructor and/or professor gives you a bad/low score you won't blame anyone of us?