IP phones connected to Cisco switches just reboot for some reason

[mszodiac19]

Hi Everyone,

We have Mitel phones connected to 3750s.  All IP phones just reboot randomly for some reason.  The IP phones are on a different vlan than the PBX controller.  There are no obvious error logs and/or reboots on the router (2900), switches and the PBX controller.  No bandwidth congestion either.  PoE is good.

We're in a loop on this.  Are there any other logs on the Cisco devices that I can check?

[Charles Hill]

Try disabling cdp on the cisco 3750, if its running.  CDP may not be playing nice with the Mitel phones.

To disable it on a port, type

config t

int g0/1

no cdp enable

To disable cdp globaly, type

config t

no cdp run

show power inline  (to verify inline power)

How often does your dhcp lease expire? 

I read a posting that stated Mitel phones were rebooting when the dhcp lease expired/renewed.

Try setting a static ip address on a Mitel phone and see if that phones stops resetting.

Hope this helps. If so, please rate.
 

[mszodiac19]

Thanks cehill.  I'll wait to see if the problem shows up again then try disabling cdp then.  The power inline shows good.

The DHCP lease expires every 8 days.  The server team just confirmed the IP phones all have different dates/time of leases which doesn't explain why the phones rebooted at the same.

I will also set a static IP on one of the phones.

[Charles Hill]

With all phones rebooting at the same time, it may be a power supply going bad.  Does the 3750 have 1 or 2 power supplies?

To rule out a power supply issue, you could always use a power brick on a phone, if you have one.

Are there other 3750 swtiches with phones?

Switch/Phones may be losing connectivity to the Mitel Controller.

[mszodiac19]

It looks like the problem has to do with PCs with NIC chipset I217-LM.  The chipset causes an IPv6 multicast storm when in sleep state.  The solution is to upgrade the driver to 19.0.

We've had new PCs (Lenovo, HP800ed) installed recently with the faulty chipset driver.  2 sites had 15 minute LAN outages!

[Charles Hill]

We may consider disabling ipv6 on our new pcs since we are not using ipv6.

It's good to know.  Thank you for the update!

Where would a ipv6 multicast storm stop?

Our network consist of multiple vlans within multiple vrfs.  In order for traffic to route from one vrf to another vrf, it has to go to our ASA, then the traffic is forwarded to the destination vrf and back to our network, if allowed.