When a computer is put to sleep the phone's network connection drops

[pbottone18]

After a lot of trouble shooting I have discovered that I can get an Cisco 8851 to drop the network connection right after I press the Sleep key on the keyboard. This is becoming a problem as because if the computer sleeps for too long the phone will become unregistered.

I have performed a packet capture from the phone to the computer, from the phone logs and from the network switch port.

All of which has not yet given up the answer to why this is happening.

I have turned off "Auto Synchronization", I've left it on, I've factory reset the phone, I've turned off CDP on the phones (we don't use CDP in our environment just LLDP).

The only way to stop this is to go into Windows 10 (21H1) power settings and make sure sleep is turned off on all power settings.

This is happening on new computers, Dell optiplex, HP mini, Microsoft surface, etc

I have opened a TAC case for this issue but was wondering if anyone else is having the same issue

The customers complaints range from not able to make a phone call to my phone says "detecting network".

Every time I talk to a customer that has this issue they a pressing sleep or the computer goes to sleep after X period of time

[Maren Mahoney]

Spitballing here: Is it possible that the "Energy Efficient Ethernet (EEE)" settings on the PC port and the Switch Port on the phone configuration page (and/or Enterprise Phone Configuration and/or Common Phone Profile) are an issue here? The default is to have this enabled on both the PC Port and Switch Port. Are those still the settings on your phones? Are they consistent across the three places where this can be set? What happens if you Disable it for the Switch Port?

The setting is supposed to be for automatic down-powering, but I can see Sleep on the PC generating some kind of weirdness causing the Phone to react.

Two other questions:

Does this only happen on sleep or also on shutdown of the PC?

What firmware are you running on the 8851s?

Maren

[mbrackett2994]

On the properties page of your network card go to power settings and uncheck the box that allows the power saver to turn off nic.  This will allow the computer to sleep but keeps the network card to keep network connection alive so the phone stays registered

[pbottone18]

Did this did not make a difference. Other than the IP address changed

By the way we use three servers as DHCP systems across our network

[pbottone18]

A few things to keep in mind are:

1. We do not use CDP throughout our network we use LLDP
2. I have turned off the power setting on the computer and it still does the same thing
3. We can trigger a reset and network stack refresh just but changing the computer from 100mb to 1gb (moving the network card to another computer that uses 100mb)
4. All of the computers are in Auto mode and all of the network ports on the switches are in auto mode

Paul

[pbottone18]

This happens on both sleep and shutdown we are running 14.0(1)SR2

[pbottone18 · Accepted solution]

We have finally fix our issue by doing the following:

1. Turning off Autosyncronization on all of the phones now 8851's
2. if this did not fix the issue then we would turn off the power saving mode on the computer

We have also upgraded all of our switches to 1gig ports this also helped in most cases