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Good morning everyone,

Just recently signed up for the site because I'm looking for some help with an issue that's been plaguing me for about a week now. I hope I'm posting in the right place. If not, then my apologies. Anyways, on to the question.

The company I work for has their VoIP service hosted through 8x8. The Cisco phones we have are SPA504G's provided through them. The issue is, I can get the phones to connect to the network and I can get them configured to connect to 8x8's service. Once they pull their profile from 8x8's system and reboot, they come back up and appear to work just fine. After about 30 seconds to a minute, all lines loose connection and the phone reboots again. When it comes back up, they can no longer connect.

We have Two VLAN's, one for data and one for VoIP, and we use CDP and LLDP on our ASA to dynamically assign which VLAN a device connects too. The ASA is also configured in such a way that VoIP phones will not work on the Data VLAN, and Computers will not be able to reach anything on the VoIP VLAN. When the phone performs that last reboot and comes back up, CDP and LLDP are both off. I turn them back on and reboot the phone. When it comes back up, it works fine for about 30 seconds and then it happens again. I try to manually assign the VoIP VLAN in the phone and assign a static IP, leaving CDP and LLDP off, but the phone won't be able to connect back to the network at all. It'll either sit at Initializing Network or Checking DNS. Any help regarding this matter would be greatly appreciated.

Router: Cisco ASA5505 | Switch: Cisco Small Business 48 port | Phone: Cisco SPA504G

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