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Grandstream GXP2120

You do not need to dial any numerical prefix before dialing an extension or external number. Simply dial the extension or 10 digit number.

Call Forwarding

1. Dial:

  • *72: Forwards all incoming calls (All/Unconditional).
  • *92: Forwards calls that arrive when you’re already in a call (Busy).
  • *90: Forwards all unanswered incoming calls (No Answer/Delayed).

2. Enter the internal extension or external number to which calls will be forwarded.

3. Press the Ok softkey (to disable call forwarding, dial *73 All/Unconditional, *91 Busy, or *93 No Answer/Delayed).

Do Not Disturb (DND)

Enabling DND stops your phone from ringing and sends all incoming calls directly to voicemail.  Calls are logged in your Missed Calls.

1. When the phone is idle, press the DND key to enable/disable.

Voicemail Access

1. Dial .

2. Dial your password (default 0000).

Speed Dial

Please contact your system administrator regarding your speed dial assignments.

3-Way Calls

1. While on an active call, press an unprogrammed LINE key to place the current call on hold and initiate a new call.

2. Dial the internal extension or external number to add to the conference.

3. Press the SEND key.

4. Wait for the second party to answer, and then let them know that you would like to add them to a 3-way call.

5. Press the CONF key and then press the flashing LINE key to merge the calls.

Warm Transfer

Places a current call on hold and allows you to speak with the other party before transferring the call to them.

1. Press an unprogrammed LINE key to place the current call on hold and initiate a new call.

2. Dial the internal extension or external number.

3. Speak with the destination party.

4. Press the TRANSFER and then press the flashing LINE key of the call that is on hold.

Blind Transfer

A blind transfer routes a call to another party without speaking to them first.

1. While on an active call, press the TRANSFER key.

2. Dial the internal extension or external number.

3. Press the SEND key.

Tip: To transfer a call directly to voicemail, dial 0 + extension.


1. Press HOLD.

2. Press the flashing LINE key to retrieve the call.

Modify Ringtone

1. Press the MENU key.

2. Select Preference > Ring Tone.

3. Select the desired ringtone (highlight to sample ringtones).

4. Press the MENU key.

Note: This device does not support silent ringtones.

Presence Monitoring

In order to presence monitor, you must have the feature enabled on your device by an administrator. If not enabled, contact your system administrator for assistance.

Note: The lines that you wish to monitor must be speed dial assignments on your phone.

*Softkeys are buttons located around the display whose function changes depending on the context. These keys are managed by your system administrator.

See a feature you don’t understand? See our phone feature glossary.

Call Handling Features

  • Warm Transfer
  • Blind Transfer
  • Do Not Disturb (DND)
  • Call Forward All
  • Call Forward Busy
  • Call Forward No Answer
  • Reject

*On the g.729 codec Grandstreams are only able to join conference calls.

  • Hold
  • Multi-way Calling*
  • Anonymous Call Rejection
  • Call Waiting
  • On-hook Dialing
  • Speakerphone

User Interface Features

  • Call Logs
  • LDAP Directory*
  • Electronic Hook Switch (EHS)

*Not centrally provisionable.

  • On Device Directory
  • Adjustable Ringer Volume
  • Bluetooth

Feature Keys

  • 6 SIP Account
  • 6 Upper Multifunction Keys*
  • 7 Lower Multifunction Keys

*Supports line assignments.

  • Voicemail Button
  • Mute Button


  • Black & White Display
  • Message Waiting Indicator (MWI)
  • Caller ID (CID)
  • Busy Lamp Field (BLF)
  • Time/Date Display
  • On-Screen Message Display

Network & Provisioning

  • PC Connection
  • Web Interface Provisionable
  • On Device Ethernet (PoE)


  • Wired Headset

Before you begin:

  1. Verify a device profile has been created.
  2. Verify the phone’s MAC address has been assigned to the device profile.

1. Press .

2. Select Status and then write down the phone’s IPv4 Address.

3. Open an incognito window in Google Chrome, type the IPv4 address into the address (URL) bar, and then press Enter on your keyboard.

4. Log in with: Username = admin and Password = admin.

Note: If this password is not accepted, contact Customer Support for assistance.

5. Go to Settings tab > Advanced Settings.

6. Enter ‹domain› for the Config Server Path.

Note: Replace ‹domain› with your unique domain (found in parentheses at the top of the admin dashboard).

7. Press [Update] > [Reboot].

Note: If the phone doesn’t automatically reboot, you must power cycle the device to apply its provisioning settings.

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