External network access background failed

## Prerequisite Verification
Ensure that the intranet access is normal.
Access [ http://intranet IP:8182]()  via a browser on the server locally to confirm that the backend login page can be opened normally.
If intranet access failsIntranet issues need to be resolved firstrefer to the documentSolutions for Intranet Access Issues.
## Common Reasons for External Network Access Failure
External network port not open
SymptomExternal network access to  [ http://public IP:8182]() times out or fails to connect.
**Solution：**
**Router/NAT device：**
Log in to the router management interface and configure Port Forwarding to map the external network port 8182 to the internal servers port 8182.The configuration path varies for different routers and is usually located in the “Advanced Settings” or “Security/NAT”  menu.
**Cloud server security group：**
In the cloud platform console （Alibaba Cloud,Tencent Cloud,AWS,etc.）,check the security group rules to allow inbound TCP port 8182 from the external network.ExampleThe security group rules should include access permissions for 0.0.0.0/0 or a specified IP range.
**Server firewall not allowing external IP：**
Symptom：Accessible from the intranet,but external requests are blocked by the server firewall.
Solution：

```bash
# Linux (using firewalld)
firewall-cmd --zone=public --add-port=8182/tcp --permanent  
firewall-cmd --reload
# Linux (using ufw)
ufw allow 8182/tcp
# Windows (run as administrator)
netsh advfirewall firewall add rule name="LarkXR_Admin_External" dir=in action=allow protocol=TCP localport=8182

```

**Public IP or domain name resolution error:
Symptom:**
Access via domain name fails,but access via public IP succeeds.
**Solution:**
Check if the domain DNS resolution points to the correct public IPverify using`nslookup domain name`or`dig domain name`.If using a cloud service providers load balancer,ensure that the listener configuration is correct.
## Quick Verification Steps
External network connectivity test

```bash
# Execute from an external device (replace with the actual public IP)
telnet public IP 8182  # If it returns "Connected," the port is accessible
curl -v http://public IP:8182  # View detailed response

```

Check port mapping
Log in to the router or cloud platform console to confirm that the external port 8182 has been correctly mapped to the internal server.
## Other Precautions
Avoid interference from VPNs or proxiesTurn off local VPNs and proxy tools before testing.Filing and complianceIf the server is located in Mainland China,ensure that the domain has completed ICP filing;otherwise,cloud providers may block external network access.