There are many things in this world that are hidden just beneath the surface that make our lives easier.  Whether it be the Secret Menu at In-n-Out Burger or the good old Konami Code, the good stuff that we need is often just out of reach unless you know the code.  This is also the case when dealing with Cisco phones.  There are three key combinations that will help you immensely when configuring these devices, provided you know what they are.

1.  Unlock Settings – *, *, #.  When you check the settings on a Cisco phone, you’ll notice that you can look at the values but you can’t change any of them.  Many of these values are set at the Cisco Unified Communications Manager (CUCM) level.  However, once common issue is the phone not being able to contact the CUCM server or the phone having the wrong address/TFTP server information from DHCP.  While there are a multitude of ways to correct these issues in the network, there is a quick method to unlock the phone to change the settings.

• Go to the Settings page of the phone
• While in the settings page, press *, *, # (star, star, pound) about 1/2 second apart
• The phone will display “Settings Unlocked” and allow you to make changes

It’s that easy.  There won’t be a whole lot to do with the phone Telephony User Interface (TUI), but you can make quick changes to DHCP, IP address, or TFTP server address entries to verify the phone configuration is correct.  By the way, when putting in an IP address via TUI, the “*” key can be used to put a period in an IP address.  That should save you an extra keystroke or two.

2.  Hard Reset – *,*,#,*,*.  Sometimes, you just need to reboot.  There are a variety of things that can cause a phone to need to be reset.  Firmware updates, line changes, or even ring cadence necessitate reboots.  While you can trigger these from the CUCM GUI, there are also times that they may need to be done from the phone itself in the event of a communications issue.  Rebooting is also a handy method for beginning to troubleshoot issues.

But Tom?  Why not just pull the network cable from the back of the phone?  Won’t disconnecting the power reboot?

True, it will.  What if the phone is mounted to the wall?  Or if the phone is running from an external power supply?  Or positioned in such as way that only the keypad is visible?  Better to know a different way to reboot just in case.  Here’s where the reboot cheat code comes in handy.

• Go to the settings page of the phone
• Press *,*,#,*,* (star, star, pound, star, star) about 1/2 second apart
• The phone will display “Resetting” and perform a hard reset

This sequence will cause the phone to reboot as if the power cable had been unplugged and force it to pull a new configuration from CUCM.  Once common issue I find when entering this code is the keypresses not registering with the phone.  Try it a couple of times until you develop a rhythm for entering it about 1/2 second apart.  Much more than that and the phone won’t think you’re entering the code.  Quicker than that and the keys might not all register.

3.  Factory Reset – “1,2,3,4,5,6,7,8,9,*,0,#”.  When all else fails, nuke the phone from orbit.  It’s the only way to be sure.  Some settings are so difficult to change that it’s not worth it.  Or you’ve got a buggy firmware that needs to be erased.  In those cases, there is a way to completely reset a phone back to the shipping configuration.  You’ll need access to unplug the power cable, as well as enough dexterity to press buttons on the front as you plug it back in.

• Unplug the power from the phone.
• As you plug it back it, press and hold the “#” key.  If performed correctly, the Headset, Mute, and Speaker buttons in the lower right corner will start to flash in sequence.
• When those three buttons start flashing in sequence, enter the following code: 1,2,3,4,5,6,7,8,9,*,0,#.  You’ll notice that’s every button on the keypad in sequence from left to right, top to bottom.
• Phone will display “Upgrading” and erase the configuration.

Don’t worry if you press a key twice on accident.  The phone will still accept the code.  However, you do need to be quick about things.  The phone will only accept the factory reset code for 60 seconds after the Headset, Mute, and Speaker buttons start flashing in sequence.

Tom’s Take

I find myself using these cheat codes all the time.  Whether I’m correcting a bad TFTP server entry or setting a static IP on a subnet, the ability to manipulate a phone without resorting to using CUCM all the time is very useful.  You can also use these codes to impress your friends with your intimate knowledge of the way Cisco phones work.  Just be careful with that reset code.  About every 1 out of 1,000 times it gives you 30 lives instead.