SFE2000P - Interface reset on DHCP renew?

Unanswered Question
Jul 9th, 2010
User Badges:

As anyone experienced this problem:

Im running POE for Cisco 504G phones with a PC attached to the LAN switch port on the phone.  DHCP is being served through a Cisco 1800 series router.

It seems that the interface will shutdown and come right back on at DHCP renewal obviously resetting the phone and causing the PC client to disconnect.  The only reason I noticed this is because it is right at the same time the lease is expiring.  Both the phone and the PC are on the same VLAN.



  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
David Hornstein Mon, 07/12/2010 - 09:05
User Badges:
  • Gold, 750 points or more

Hi Domenick,

You are running a SFE200P connected to a Cisco 1800 router.

Is this some sort of Hosted SIP solution ?

Have you made sure you are using the most currently available software 7.4.4 for the SPA504G phone ?

release notes that I have attached show the phone will reboot with the older code when a certain condition is met, but that issue was fixed with 7.4.4.

What does the log of the SFE2000P indicate, that E(port number) has gone down  or does it indicate something within the switch might be causing the port to go down.

To be safe, also let me know what version of SFE2000P code you are running, it should be version

regards Dave

dlandriscina Mon, 07/12/2010 - 10:33
User Badges:

Hi Dave,

I am running 7.4.4 on the SPA 504G and the SFE2000P is running - is there a known issue with interface resets on .16?

I checked the log , it just states link down, then link up.  The only thing running on the switch is STP.  Its so odd - i have never experienced this. I even went as far as changing the dhcp lease times on the router.



David Hornstein Mon, 07/12/2010 - 11:32
User Badges:
  • Gold, 750 points or more

Hi Domenick,

The question in my mind, is how would a lease renewal on a phone going to  cause the port to go down.  I'm not sure what you mean by .16, but if it is port number 16 no, should be no problem, it's not a special port.

I'm guessing that the SFE2000P is not in stacking mode  or Layer 3 mode (checked via telnet or console). 

By the sound of the error log when the link goes down and up again, sure sounds like the phone is going down and up.

You have an option to see what the phone is doing by sysloging information from the phone to a syslog server, such as the kiwi-syslog daemon.

Sure sounds like the phone is dropping and not the switch port, I may be wrong, a syslog of what's happening with the spa504G might be useful.

I have attached the admin guide that shows how to set up the unit for local or remote  syslog server and sending debug messages to the syslog server.  This might be informative, but it sure sounds like you should open a call with the Small Business Support center  as well.


regards Dave

dlandriscina Mon, 07/12/2010 - 21:04
User Badges:

the .16 was meant to say that I am running that version of the firmware on the switch.  I installed the syslog server and I will let you know what it says as soon as the link goes down.

Thank you


This Discussion