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5200 series switch....

IP phones here locally will not pull a DHCP address...SOMETIMES...

However, one look at the DHCP log files and it 'assigns' an address to the phone.

Any flags in the system? This appeared to be working normally until other sites came on board.

Should there be an entry in DNS for the 5200?

When the IP fones do not get an IP address, what does the fone LCD screen read?

Yer 5200 should have a DNS entry so it can utilyze NTP to keep it's time correct.

NO DHCP RESPONSE
RESETTING IN 45 SECONDS

Then it of course counts down, gives me a 'bogus' IP addy...

I'll add the PTR to DNS

The 'bogus' addy is it's static IP address. Sounds like either yer DHCP server is slow or your network is. One pretty easy thing to check is whether your ethernet switches have a management interface. If they do, check if 'Spanning Tree' is turned on. If it is, try turning it off. Sometimes the same feature is called 'Edgeport'.

which IP phone is it?

normally.. the IP phone will get DHCP locally.. once the phone connected to the IP card, IP Card will tell phone to either use a specific IP or DHCP or whatever. then reboot... checked the IP card settings?

Turn spanning tree off on the switchports connected to your phones and give that a try.

It can take over 50 seconds for the switchports to set to Fast Ethernet, by which time the phone has reset... sometimes if you just let it go for a while the switchport will set before the phone resets and you'll get your ip address.

Here are some ideas.

Here is a small free utility that queries a network for DHCP servers and lists all the responses received.

https://www.roadkil.net/dhcpfind.html

It displays all the DHCP servers on your network and what settings they are handing out. It doesn't really time DHCP response but you can kind of get a feel for it by watching the responses come in.

You can also use the free Wireshark to watch the network traffic on your interface, filter out DHCP, and time exactly how long DHCP responses take to receive.

Finally, if your IP sets run 2.02 or later firmware you can connect to one with web browser, log in and set port mirroring on. This uses the 'PC' ethernet port as a mirror for the 'LAN' port. Hook up a laptop running wireshark and you can see all the packets sent and received by the IP set.

In our environment we use Adtran Netvanta switches for POE and have about 130 IP sets pulling DHCP from one of the Netvantas. We have not had issues where a IP set takes so long to get a link and pull DHCP that it resets. It's pretty stable.

Is it possible you are running out of IP addresses in your DHCP pool?

You also didn't mention what brand and make of switches you are connected too. There are some known issues with a few different brands out there.

dhostetter,

I was playing with the dhcpfind.exe application and that is a nice little app.

I have been looking for something that also displays all of the scope options in that offer as well if anyone has come across an app like that.