Mitel phone going dead every 10-15 minutes...

[dyelton]

We have over 100 Mitel 5224 and 5330 phones connected via Dell PowerConnect POE switches to an Inter-Tel 5000 system. We've had an issue where two of the phones (connected to completely different fiber lines and POE switches) would display a blinking cursor followed by two hypens every 10-15 minutes (see attached photo) and stay that way for ~5-10 minutes.

It seems that the issue follows the phone. When the issue occurs the phones never lose power (POE). All phones are running the same firmware and are setup the same way (with the exception of a different static IP address...no DHCP on any of the phones).

If you dial the extension of a phone having the issue you get "*phone name* IS UNPLUGGED" displayed on the calling phone.

Is there a logical explanation for this? I'm all out of ideas.

 

[slapin]

STP on switches. Port speed mismatch. Trunking issues.
If you see this simptoms on all the phones at the same time I would assume uplink to ICP issues.

 

[dyelton]

It isn't a port speed mismatch issue and I'm pretty sure it isn't a trunking issue either. We do have STP enabled on all of our switches but I haven't done anything with it as the default on the switches is to have STP enabled. These are Dell PowerConnect 3524P/3548P and 6248P switches.

Will it have any averse effects if I disable STP to see if the problem goes away? I know STP must be enabled on all switches in a network for it to function properly but if I disable it on one switch for testing will this work in taking STP out of the equation as a problem? Will disabling STP knock anyone off the network (particularly anyone using the phone system that's going over these switches)?

Thanks!

 

[slapin]

If you don't have loops or redindant links in your network, then STP can be safely disabled