Troubleshooting guide
Diagnosing Problems
195
Enabling or Disabling 802.1X Authentication
By default, EAP- MD5 Challenge Authentication Protocol is enabled on 5215 Dual Mode, 5220 
Dual Mode, and 5235 IP Phones. If your network does not use this protocol, you do need to 
disable support for it on these phones.
1. Access the configuration menu. See page 188.
2. From NETWORK PARAMETERS? press No until on the telephone keypad until TOOLS 
AND FEATURES? appears.
3. Press Yes.
4. Press No until EDIT 8021X SETTINGS appears.
5. Press Yes. ERASE 8021X DATA? appears in the display.
6. Press No. If currently enabled, you are prompted to disable 8021X. If currently disabled, 
you are prompted to enable 8021X.
7. Press Yes.
8. Press Yes. The phone erases the data from its flash and then reboots.
IP Phone Boot Sequence
After you connect an IP Phone to the network, it goes through the following boot sequence (this 
applies to Release 5.0 and later):
Note: The IP phone username and password that you configured for EAP-MD5 
Challenge Authentication do not need to be reprogrammed if power to the phone is lost.
Tip: MAC Addresses, and Main and Boot versions in the following table are examples for 
illustration purposes. The numbers displayed at the install site may be different. The x’s are IP 
Address, VLAN, and Priority place holders.
Table 64: IP Phone Boot Sequence
Boot Sequence Phone Display
1. Waiting for an Ethernet link to be established. Waiting for LAN link
to come up
2. If an Ethernet link is not established, continue with the bootup 
process.
Bad LAN link
Check Ethernet cable
3. The first stage for bootup.
Note: Refer to Table 65 on page 198 for 802.1x Port Access Control 
messages.
08-00-0F-AA-BB-CC
Booting: 04.02.01.06
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