IAD101H version: V300R001C03SPC400
Networking: The WAN port of the IAD was connected to a switch upstream, and the LAN port was connected to a PC downstream. The IP address of the IAD was 192.168.186.37, and the IP address of the downstream PC was 192.168.186.60.Symptom: The voice users connected to the IAD could use services normally, but the downstream PC could not access Internet.
Huawei performed the following operations to handle the problem:
1. Connected the PC to the upstream switch directly without changing the PC's IP address. The result indicated that the network was normal.
2. Pinged the gateway from the PC, and the operation failed. Pinged the IAD from the PC, and the operation failed.
3. Checked the NAT status on the IAD and found that the NAT function was disabled.
4. Checked related documents and found that, according to the documents, the nat disable command could not only disable the NAT function, but also enable the lanswitch function (that is, running the nat disable command was equivalent to running the lanswitch mode command in lanswitch mode).5. Ran the lanswitch mode command after running the nat disable command, as suggested by R&D engineers. The result indicated that the network was normal.
Possible causes were as follows:
1. The network had a problem.2. The NAT function was enabled for the IAD, but a static IP was configured for the PC (if the NAT function is enabled for the IAD, downstream data users can only obtain IP addresses from the IAD automatically, and no static IP addresses can be configured).
IAD V300R001C03 (SPC100-SPC600) documents has an error. The nat disable command can only disable the NAT function, but not enable the lanswitch function. To enable the lanswitch function, run the lanswitch mode command in lanswitch mode.
By default, the NAT function is disabled on the IAD. If you need to configure static IP addresses for downstream data users, run the lanswitch mode command in lanswitch mode. Otherwise, the gateway cannot be pinged.If the NAT function has been enabled, run the nat disable command and then the lanswitch mode command.