DHCP-IP Phones only

[DigitelD]

I had this set on a BCM400 4.0. The BCM is on the customers network. The problem is that the PC's were being given strange addresses through DHCP instead of the configured addresses from their DHCP server. They disconnected the BCM from the network, restarted the PC's and all was well. My understanding is that the BCM will not hand out IP addresses to any device but IP phones only. Has anyone had any experience with this?

SHK Certified (School of Hard Knocks)

 

[bluemr2]

There is a setting for "IP phones only." Is that how you have it configured? If you have DHCP enabled it will serve addresses to all devices. I have used the IP phones only before without interfering with their DHCP server.

 

[DigitelD]

Yes, that is my point. I have the DHCP as "IP phones only" and the IT guy is stating strongly that the BCM is handing out IP addresses.

SHK Certified (School of Hard Knocks)

 

[madwok]

If you activate DHCP on the BCM, first make SURE that your range are not overlapping with the other DHCP server .

I saw some other devices ( non PC ) also can get the IP's from BCM even it is set at "IP only" as I watch them on my sniffer.
Not all vendors are following strict rule in their protocol stack.

I personally will not ever turn on DHCP on BCM , let the IP set get its IP from the corporate DHCP server . You don't get nothing but headache by turning DHCP on the BCM.

I had over 1500 of them IP sets in my WAN and they all use partial DHCP without any problem in US/India/UK .

 

[gm85]

Do the addresses start with 169.254.x.x?

The workstations fallback to that address if they're configured to use DHCP, however they are unable to obtain an address.

They use 169.254.x.x since a computer still needs a legitimate address (0.0.0.0 is invalid) even if it is unable to obtain one from the DHCP server.

 

[DigitelD]

I am out of town and I could not get that info. My understanding is that when this setting is "IP Phones only" the BCM will only hand out IP addresses on port 7000. If their PC's try to pull from this port then they will receive an IP address.

SHK Certified (School of Hard Knocks)