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Help needed: 1 phone comes up, 1+ go down

Hi all

We have a strange phenomenon going on at on one of our sites. What happens is this: we connect a few phones to the network and more or less at the same time the same number or more go down elsewhere on the floor with the 'Ethernet Disconnected' message displayed. There is no pattern to this, the phones that drop off are seemingly random.

It's not a power issue as the phones don't actually power down they just appear to lose their network connection.

It can't be DHCP as my understanding of DHCP is not compatible with this behaviour.

I would find it hard to believe its congestion as it's a 1Gb LAN and WAN with around 200 phones.

Initial thoughts are bad cabling but I've experienced poor cabling before and never seen something like this.

Any suggestions from the community?

Many thanks

Everyone's tags (2)
VIP Purple

Help needed: 1 phone comes up, 1+ go down


try to run below commands  for PoE to check any power related issue.

a. debug ilpower powerman

b. show power inline



Help needed: 1 phone comes up, 1+ go down

Hello Aman

Thanks for your swift reply. Unfortunately we cannot run a debug as it's a production box. I have checked power and that doesn't appear to be the issue as all output related to power is showing as sufficient power available. I could be wrong so would welcome any clues to look for in the output that I may have missed.

I only say it's not power related because the phones don't power down, they just lose network connectivity.

Thanks again and I look forward to more helpful suggestions.


VIP Purple

Help needed: 1 phone comes up, 1+ go down

Hi Devlin,

Can u refer the link for TDR results:



Re: Help needed: 1 phone comes up, 1+ go down

Thanks Aman

I'll aim to get the output tomorrow if possible.


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