Cellular Management

Overview

Arrow devices include integrated LTE cellular modems that provide backup connectivity when primary ethernet connections are unavailable. The cellular connection ensures your Arrow devices remain accessible even during network outages.

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Viewing Cellular Status

Access cellular status through the Arrow Manager dashboard on your device. The Cellular Status card displays real-time connection information.

Connection Status

Status	Meaning
Connected	Cellular is online and can route traffic
Registered	Modem is registered with carrier but may not have data
Disabled	Cellular is intentionally turned off
Disconnected	No cellular connection available

Routing Status

When cellular is connected, an additional badge indicates routing status:

Badge	Meaning
Active Route	Cellular is actively routing network traffic
Backup	Connected but ethernet is handling traffic

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Understanding Cellular Metrics

Signal Strength

Signal strength is displayed in dBm (decibel-milliwatts):

Range	Quality
-50 to -70 dBm	Excellent
-70 to -85 dBm	Good
-85 to -100 dBm	Fair
-100 to -110 dBm	Poor
Below -110 dBm	Very Poor

Advanced Signal Metrics

Metric	Description	Good Values
SINR	Signal-to-Interference-plus-Noise Ratio	> 10 dB
RSRP	Reference Signal Received Power	> -80 dBm
RSRQ	Reference Signal Received Quality	> -10 dB

Connection Details

Field	Description
Carrier	Mobile network provider
Mode	Connection type (LTE, 5G, etc.)
Band	Frequency band in use
IP Address	Internal cellular IP
Public IP	External IP seen by internet services
Latency	Network round-trip time in milliseconds
Download/Upload	Current connection speeds

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Automatic Failover

Arrow devices automatically manage cellular connectivity based on ethernet status:

flowchart TD
    A[Ethernet Connected] --> B{Has Internet?}
    B -->|Yes| C[Cellular: Backup Mode]
    B -->|No| D[Cellular: Active Route]
    E[Ethernet Disconnected] --> D
    D --> F[Traffic Routes via LTE]
    C --> G[Traffic Routes via Ethernet]

When Cellular Activates

Cellular becomes the active route when:

• Ethernet cable is disconnected
• Ethernet is connected but has no internet access
• Primary network gateway is unreachable

When Cellular Returns to Backup

Cellular returns to backup mode when:

• Ethernet regains internet connectivity
• Primary network gateway becomes reachable

Default Route Interface

The Arrow Manager shows which interface is currently handling traffic:

Interface	Meaning
vmbr0	Ethernet bridge is active route
wwan0	Cellular modem is active route

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LTE Bridge Mode (Advanced)

LTE Bridge Mode creates a dedicated network bridge that routes virtual machine traffic through the cellular connection. This is an advanced feature for specific use cases.

Cost Warning

LTE Bridge Mode incurs a $20 per gigabyte data fee. This mode should only be used for temporary testing or emergency access. Normal operation should use ethernet connectivity.

When to Use LTE Bridge

• Emergency access when ethernet is completely unavailable
• Temporary testing requiring isolated internet access
• Specific scenarios where VM traffic must use cellular

Bridge Status Indicators

Component	Description
Bridge Mode	Enabled or Disabled
vmbr1 Interface	Whether the LTE bridge interface exists
LTE Connection	Whether wwan0 is active
NAT Rules	Whether network translation is configured
Active VMs	Number of VMs attached to vmbr1

Enabling LTE Bridge

1. Access Arrow Manager on your device
2. Navigate to LTE Bridge Mode settings
3. Verify the LTE connection is active (required)
4. Click Enable LTE Bridge
5. Confirm the cost warning in the dialog

Disabling LTE Bridge

1. Navigate to LTE Bridge Mode settings
2. Click Disable LTE Bridge
3. Confirm the action

VMs attached to vmbr1 will lose connectivity until reconfigured.

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Configuring VMs for LTE Bridge

To route a VM through the LTE bridge:

In Proxmox

1. Enable LTE Bridge Mode in Arrow Manager
2. Edit your VM’s hardware settings
3. Change the Network Device bridge from vmbr0 to vmbr1
4. Save and restart the VM

Inside the VM

Configure network settings using one of these methods:

DHCP (Recommended)

Set your VM’s network interface to DHCP. It will automatically receive:

• IP Address: 192.168.2.10-250
• Gateway: 192.168.2.1
• DNS: Provided by DHCP

Static IP (Optional)

Setting	Value
IP Address	192.168.2.X (2-254)
Subnet Mask	255.255.255.0
Gateway	192.168.2.1
DNS	8.8.8.8 (or preferred)

Verify Connectivity

Test the connection from inside the VM:

curl ifconfig.me

This should return the cellular public IP address.

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LTE Bridge Architecture

flowchart LR
    subgraph Arrow Device
        VM[Virtual Machine] --> vmbr1[vmbr1 Bridge<br/>192.168.2.1/24]
        vmbr1 --> NAT[NAT Rules]
        NAT --> wwan0[LTE Modem<br/>wwan0]
    end
    wwan0 --> Internet[Internet]

How It Works

1. vmbr1 Bridge: Created with IP 192.168.2.1/24
2. DHCP Server: Assigns IPs (192.168.2.10-250) to VMs
3. NAT Rules: Translates VM IPs to the LTE interface
4. IP Forwarding: Enabled between vmbr1 and wwan0
5. Auto-Disable: Bridge disables if LTE connection drops

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Troubleshooting

Cellular Shows Disconnected

Possible Causes:

• No cellular signal in location
• SIM card issue
• Modem hardware problem

Resolution:

1. Check signal strength in a different location
2. Verify SIM status with VTEM Labs support
3. Restart the Arrow device

Cellular Connected But No Internet

Possible Causes:

• Data plan exhausted
• Carrier network issues
• APN configuration problem

Resolution:

1. Wait for carrier network recovery
2. Contact VTEM Labs to verify data plan status
3. Check if other cellular devices work in the location

LTE Bridge Won’t Enable

Possible Causes:

• LTE connection not active
• Previous bridge configuration failed

Resolution:

1. Verify “LTE Connection” shows as active
2. Try refreshing the status
3. Restart Arrow Manager if needed

VM Can’t Connect Through LTE Bridge

Possible Causes:

• VM not attached to vmbr1
• Incorrect network configuration in VM
• Bridge not fully enabled

Resolution:

1. Verify VM network device is set to vmbr1
2. Check VM has IP in 192.168.2.x range
3. Verify all bridge status indicators are green
4. Test with DHCP before using static IP

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Related Documentation

• Arrow Manager Network - Network status and management
• VPN Management - VPN connectivity
• Device Management - Managing Arrow devices