Please document the tftp boot process and steps to resolve the message "cannot contact boot server"
the boot process related to kickstart?
Current boot loader on the phones is failing to honor the LLDP-provided Voice VLAN. Once it fails and proceeds with the existing configuration, the SIP application firmware correctly honors the LLDP and reconnects to the network on the correct VLAN to load all of the config files for the phone. This condition causes a delay during boot, an annoying message on the screen, and prevents automated firmware upgrades. It does not prevent the provisioning of the actual phone configuration though. The new boot loader which is required for the firmware I'm testing in bug 1119958 has been verified to fix this issue.
This should have been fixed by bug 1119958.