Connecting IP phone to a Cisco SG110-24HP-NA unmanaged switch.

[tmm1967@gmail.com]

I have a SG110-24HP-NA unmanaged switch, purchased used cisco IP phones model #7960 and am trying to get the phones working.  I have charter as my internet provider using a Arris TM804G modem.  Phones are not working, what am I missing?

[Iliya Gatsev]

Hi, 
My name is Iliya Gatsev from Cisco Technical Support Team.

I suppose that the the phones are configured to use VLAN different than VLAN  1. Unmanaged switches  have no configuration interface or options. They are plug and play.

If you connect the phones directly to the modem they are working ?

Please rate this post or marked as answered to help other Cisco customers.

Iliya Gatsev
Cisco STAC Network Engineer
Together we are the human network .:|:.:|:. CISCO

[mipopov]

Hello, 

The phones are getting power from SG110-24HP just fine, right?

If everything with the power is normal, I can suggest to check what image these 7940s are using.

With normal VoIP provider, most probably they should be on SIP image, just to attempt to register them.  

Cheers, 

Mike

[tmm1967@gmail.com]

When I plug the phones into the switch I do not get power on the phones.

[mipopov]

Hello,

As per datasheet SG110-24HP has only 12 ports with PoE:

https://www.cisco.com/c/en/us/products/collateral/switches/110-series-unmanaged-switches/datasheet-c78-734450.html

Power over Ethernet (PoE)

Model Name SF110D-08HP SF110D-16HP SG110D-08HP SG110-16HP SG110-24HP

Power Dedicated to PoE 32 watts 64 watts 32 watts 64 watts 100 watts

Number of PoE Ports 4 8 4 8 12

I'm attaching picture of the front - only left 12 port (with amber lights) are PoE:

So, make sure that you use these ports to max budget of 100 Watts

[wycalero]

Good Morning,

Are you connecting the phones on the PoE ports? remember that out of the 24 ports that you have on the switch only 12 al PoE.

Regards.

[tmm1967@gmail.com]

good moring, yes I am.

[mipopov]

Hello,

Power requirements  of the Cisco CP-7960G is 6.3W.

So, in normal circumstances it should work, try to check the ports with some other PD device as access point for example.

[tmm1967@gmail.com]

The only device that is plugged into the switch is 1 phone..so I do not
believe power would be the issue since there is nothing else drawing power
from it. Correct?

[mipopov]

Hello, 

Yes, I see - what I mean is that the phone can be with faulty PoE or the switch can be with faulty PoE. 

The simple check/test will be to test with some other PD 802.3af device (preferably with known working one).

[tmm1967@gmail.com]

ok, so you think maybe just the PoE ports may be faulty? What type of
device(s) can i test with in those ports?

[wycalero]

You can test an Access Point for example.

[tmm1967@gmail.com]

let me see if i can find one. Is there a number that I can reach you at or
is this the best means of communication with you?

[wycalero]

Sure, you can call to 1-866-606-1866 and open a new ticket so we can give you support over the phone.

[trophy94]

Was there a fix for this issue?  I am having the same issue with Allworx IP phones.  They get power, but will not communicate with the rest of the network.  No Ethernet Link!  Init/Load failed!