Grandstream IP Phone Setup Guide

← Hardware & Devices

Grandstream phones are fully supported on SIPSTACK Nova PBX and are a strong choice for business deployments. The GRP series in particular supports zero-touch provisioning and is designed for enterprise environments. The GXP series is widely deployed and offers reliable SIP performance across a range of budgets.

Supported Models

Series	Models	Lines	Notes
GRP (enterprise)	GRP2601, GRP2602	2	Entry-level enterprise
GRP (enterprise)	GRP2612, GRP2614	6	Mid-range, PoE
GRP (enterprise)	GRP2616	6	Color display, 24 BLF keys
GXP (business)	GXP1628	2	Compact, budget-friendly
GXP (business)	GXP2135	8	Mid-range
GXP (business)	GXP2160, GXP2170	6	Flagship GXP, color display

Recommended firmware: GRP series → 1.0.7.x or later | GXP series → 1.0.9.x or later. For DP-series DECT bases see DECT Cordless Phones.

Unboxing & Physical Setup

1. Remove the phone body, stand, handset, and handset cord from the packaging.
2. Attach the stand to the back of the phone (slot it in from the bottom — it snaps into place).
3. Connect the handset cord to the handset port on the left side of the phone.
4. Connect an Ethernet cable from your PoE switch port to the LAN port on the back of the phone.
   • If your switch does not support PoE (802.3af), use the included 12V DC power adapter.
   • The secondary PC port on Grandstream phones passes through Ethernet to a desktop computer, allowing a single wall drop to serve both the phone and PC.
5. The phone boots and displays the Grandstream logo. Allow 60–90 seconds for a full startup.

Before You Start: Your Provisioning URL and PIN

Every Nova PBX organization has one provisioning URL and one provisioning PIN that all of its phones share:

https://<slug>:<PIN>@cfg.sipstack.com/<slug>/

• <slug> is your tenant slug (also the username).
• <PIN> is your provisioning PIN — 8 digits for organizations set up since September 2026.

Both live in Switchboard → Nova PBX → System → PBX Settings → Provisioning Access. The URL is shown with the PIN masked; the Regenerate PIN button reveals a new PIN, once. The PIN is shown once when generated. Lost it? Rotate it in Provisioning Access — phones keep working on the old PIN for 24 hours.

There is no per-device password and nothing to copy from an individual phone’s page: the same URL provisions every Grandstream in your organization.

Auto-Provisioning via SIPSTACK (Recommended)

Step 1: Register the Device in Switchboard

1. Log in to Switchboard.
2. Navigate to Nova PBX → Devices → Devices and click Register device. If the page asks you to generate your provisioning PIN first, do that in PBX Settings → Provisioning Access — phones cannot be registered until the PIN has been generated.
3. Enter the phone’s MAC address — printed on the label on the back/bottom of the phone (format: C074ADXXXXXX or 000B82XXXXXX).
4. Pick Grandstream and the model, then click Register device.
5. In the key editor, assign an extension to line 1 (and any BLF / speed-dial keys you want).
6. Click Apply Changes. Applying publishes the phone’s configuration to the provisioning server — until you apply, the server has nothing to hand the phone.

Step 2: Point the Phone at the Provisioning Server

Option A — DHCP option 160 (recommended, zero-touch). Set option 160 on the DHCP scope your phones use to https://<slug>:<PIN>@cfg.sipstack.com/<slug>/. GRP and GXP phones read it on boot; if a phone ignores it, enable Maintenance → Upgrade and Provisioning → Allow DHCP Option 43, 160 and 66 to Override Server. Entry steps for Windows Server, pfSense, ISC dhcpd, MikroTik and FortiGate are in DHCP Option 160: Provisioning URL for Nova PBX Phones.

Option B — enter it in the web UI. Grandstream phones are most reliably configured through their web interface rather than the phone menu.

1. Find the phone’s IP address: press the round navigation button on the phone → Status → Network Status. The IP address is listed there.
2. Open a browser and go to http://{phone-ip} (e.g., http://192.168.1.110).
3. Log in with username admin and password admin.
4. Navigate to Maintenance → Upgrade and Provisioning (on newer firmware the fields are on the Config File tab).
5. Set the following fields:
   • Config Upgrade Via: HTTPS
   • Config Server Path: cfg.sipstack.com/<slug> — host and slug only, no https://
   • HTTP/HTTPS User Name: <slug>
   • HTTP/HTTPS Password: your provisioning PIN
6. Click Save and Apply, then reboot the phone. It fetches its configuration from SIPSTACK and registers.

After rebooting, the phone’s screen should show your extension and a registered idle state. In Switchboard the device’s provisioning status reads Registered once its configuration has been published.

What the phone requests

A Grandstream phone asks the provisioning server for cfg<mac>.xml (its MAC address in lowercase, for example cfg000b82aabbcc.xml) — the server answers that filename with the phone’s configuration. The phone first tries the binary form cfg<mac> and then the generic cfg<model>.xml; a 404 for those two in the phone’s log is normal and harmless.

Configuring via Phone Menu (Alternative)

If you prefer to configure the provisioning URL on the phone directly:

1. Press Menu (the center navigation button).
2. Go to System → Upgrade (or Config → Upgrade on older firmware).
3. Set Upgrade Via to HTTPS and Config Server Path to cfg.sipstack.com/<slug>; enter <slug> as the HTTP user name and your provisioning PIN as the password.
4. Press the Save soft key and confirm the reboot.

After the First Provision

The configuration the phone downloads also carries the provisioning server path and username, so the phone keeps checking for updates on its own schedule. Grandstream phones do not receive SIPSTACK’s instant “reprovision” signal — after you change keys or settings in Switchboard, either wait for the next poll or reboot the phone. The PIN is never written into a configuration file; it stays in DHCP option 160 or in the value you typed on the phone. If you rotate the PIN, update DHCP option 160 (or the phone’s HTTP/HTTPS Password) within 24 hours.

GRP Series: Zero-Touch Provisioning Note

GRP phones are designed for Grandstream’s cloud management platform (GDMS), but SIPSTACK uses its own provisioning infrastructure. To use SIPSTACK auto-provisioning on GRP phones:

• Do not activate the phone through GDMS before setup — GDMS will lock the provisioning server to Grandstream’s servers.
• If the phone was previously activated on GDMS, you must release it from GDMS first (via the GDMS portal), then factory reset before pointing it to the SIPSTACK provisioning server.
• DHCP option 160 is the zero-touch path: set it to https://<slug>:<PIN>@cfg.sipstack.com/<slug>/ and GRP phones pick it up on first boot.

Manual SIP Registration (Fallback)

If auto-provisioning is not available, configure a SIP account manually:

1. Log in to the phone’s web UI at http://{phone-ip}.
2. Go to Accounts → Account 1.
3. Under the General Settings tab, fill in:
   • Account Active: Yes
   • Account Name: Any label (e.g., “Extension 201”)
   • SIP Server: Your assigned SIP server from Switchboard
   • SIP User ID: Your SIP username
   • Authenticate ID: Your SIP username
   • Authenticate Password: Your SIP password
   • Name: Display name for the extension
4. Click Save and Apply. The phone registers within a few seconds.

SIP credentials are on the extension’s SIP Auth tab in Switchboard (Nova PBX → Extensions → [extension]).

Firmware

SIPSTACK does not currently distribute firmware to phones — check and update it yourself:

1. In the web UI, go to Maintenance → Upgrade and Provisioning → Upgrade.
2. The current firmware version is displayed under Device Info.
3. To upgrade, click Upload Firmware and select a firmware file downloaded from Grandstream’s support portal. The phone reboots when the upgrade completes; its provisioned configuration is kept.

Factory Reset

After a factory reset the phone re-provisions from DHCP option 160 on its next boot; if you entered the server path manually, enter it again.

Via phone keypad:

1. Press and hold the MUTE button (or the round center button, depending on model) for 10+ seconds.
2. The screen will display a confirmation prompt for Factory Reset.
3. Confirm — the phone resets and reboots.

Via web UI:

1. Go to http://{phone-ip} and log in.
2. Navigate to Maintenance → Upgrade and Provisioning → Upgrade.
3. Click Reset and Reboot at the bottom of the page.

Troubleshooting

Symptom	Likely Cause	Fix
Line unregistered after reboot	The phone has no configuration yet: MAC not registered, no extension on line 1, or changes not applied	Verify the MAC in Nova PBX → Devices, assign an extension to line 1, click Apply Changes, then reboot the phone
Provisioning log shows 401	Wrong slug or PIN in DHCP option 160 or in the HTTP/HTTPS user name / password fields	Compare with PBX Settings → Provisioning Access; after a rotation the previous PIN stops working 24 hours later
Provisioning fails for every phone at once	100 failed attempts within an hour paused provisioning for your organization	Correct the PIN, wait for the hour to elapse, then reboot one phone before the rest
Settings changed in Switchboard but the phone is unchanged	Grandstream phones poll rather than receive a push	Wait for the next poll or reboot the phone; confirm you clicked Apply Changes
Phone stuck in boot loop	Corrupt firmware or bad configuration	Factory reset; re-provision
Web UI login rejected	Password was changed previously	Try admin/admin or user/123 (user-level login); factory reset if needed
One-way or no audio	SIP ALG enabled on router	Disable SIP ALG; see Network & Firewall
GDMS lockout on GRP model	Phone was pre-registered to GDMS	Release from GDMS portal, factory reset, then provision via SIPSTACK

For additional help, contact SIPSTACK Support at https://www.sipstack.com/contact.