More Fixes for Random Dropped Calls on the ShoreTel System

This is just a quick post about calls getting dropped and other phone related issues with the ShoreTel phone system. A lot of times it isn’t the ShoreTel hardware that’s the root problem, it is the networking equipment it is attached to. Here are some I’ve run into, and things to look for if your partner happened to also have installed your POE switches.

  1. Port Settings – If you use Cisco switches and have older ShoreTel switches (like a 40 switch, 60 switch, some old 50 switches, etc). Check the port settings on the ShoreTel switch. Set the speed to 10/100 Full Duplex. Do the same on the switch. For some reason Cisco switches and ShoreTel voice switches don’t play nice with each other. This can cause huge issues. If you are using VLANs you definitely want to make sure all your settings are manual.
    If you aren’t sure how to check this, go into ShoreWare Director and click on Quick Look, look under the site with the problem, click on one of the switches and look at the bottom of that page. On the second line from the bottom in the “Details Section” it should say “100M Full Duplex(Manual)” if it says Auto, consider changing it. Note that you should do this on the network switch port it is connected to as well.
  2. POE Issues With Cisco – This might be better now but a lot of Cisco POE switches can’t handle a full load. If you have over half your ports on a Cisco switch with a phone on them, you might consider getting another switch to put in. Netgear switches don’t seem to have this problem.
  3. POE Issues with 3COM – Reboot your switches often, sometimes 3COM switches will just deactivate POE on some ports for no reason. Just unplug and plug them back in. This might have been fixed with firmware.
  4. Dropped Calls on Netgear Switches – While I’ve not seen Netgear switches die from using every single PoE port, I have seen them do weird things on old firmware. If you’re experiencing dropped calls and the other stuff above is working right, make sure you’re running the most current firmware if you have Netgear PoE smart switches. A lot of times just upgrading the firmware will eliminate this problem, even if the dropped calls just happened recently and they have been running perfectly for several years.
  5. Factory Reset Your Phones – This is one that TAC will have you do if you call them for specific people having issues. Just refer to my article on factory resetting and you’ll be good. 

Hopefully this post has given you a few places to look and test out. If you found this information helpful please let us know!

 

2 Replies to “More Fixes for Random Dropped Calls on the ShoreTel System”

  1. FYI… you can look what the power output of the Cisco switch by running ‘show inline power’ from CLI. It will tell you what wattage is being used and what is available. Different switch models can support different wattage so make sure you have one that supports all the ports with POE not just half.

    1. That is a fair point. I didn’t mention some switches are “half PoE” where the first half of the ports are all that are actually powered. However, I’ve run into this quite often with switches where all the ports are PoE ports and putting phones on much more than half of them can cause problem. Granted this is on older Cisco switches, but so many places have super old networking equipment still installed and don’t bother refreshing until they break. I’ve even had 24 port switches where only 12 were PoE just flat quit powering more than 9 phones at a time for no discernible reason. This may be weird wattage requirements from ShoreTel, I dunno. I just know Netgear switches don’t tend to have this problem.

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